


Delays and Dates

by skerb



Series: Postcards From Waterfall [2]
Category: Undertale (Video Game)
Genre: Awkward Flirting, Caretaking, Emotional Hurt/Comfort, First Dates, Flashbacks, Haunting, M/M, Making Out, Monster Biology, Protective Sans (Undertale), Psychological Horror, Sans & Alphys Friendship, Sans (Undertale) Needs a Hug, Shy Sans (Undertale), sansby - Freeform
Language: English
Status: Completed
Published: 2017-12-14
Updated: 2018-02-14
Packaged: 2021-03-13 02:09:14
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 12
Words: 69,533
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28520679
Author URL: https://archiveofourown.org/users/skerb/pseuds/skerb
Summary: A shift, a grate, a crack, a grind.Seeking knowledge, Sans goes to Old Gerson to see what he can learn about skeletal biology - though, in the most embarrassing way possible. Undyne relays a message for him to visit Alphys.Grillby gets to flirt a little... and in turn, Sans gets to see stars.(CH 13-24 - DELAYS & DATES)
Relationships: Grillby/Sans (Undertale)
Series: Postcards From Waterfall [2]
Series URL: https://archiveofourown.org/series/2089182
Kudos: 31





	1. Chapter 1

**Summary for the Chapter:**

> A shift, a grate, a crack, a grind.
> 
> Seeking knowledge, Sans goes to Old Gerson to see what he can learn about skeletal biology - though, in the most embarrassing way possible. Undyne relays a message for him to visit Alphys.

At the sound of approaching dogs, they bashfully separated, and for a moment Sans couldn’t keep his gaze from Grillby’s face. He couldn’t stop smiling, couldn’t help the bright hopefulness that welled up in his soul and how the fire monster’s did in turn. So it was with great reluctance that Sans parted and stood, just as the door chimed. A little behind schedule, the dogs bounded inside for their nightly gathering. Quietly grinning to himself, Sans drifted to the door, staying idly by to watch Grillby. Then he gave a short wave goodbye and turned to leave.

Sans felt as though his entire soul was filled to bursting, incapable of containing the wellspring of giddiness that overflowed from deep inside of him. On the outside, Sans appeared his usual self to anyone that knew him, but on the inside he was punch-drunk. His soul swam with mushy feelings and a new appreciation for life, one full of promise. He would’ve liked to stay in Grillby’s company for just awhile longer, but the canine squad’s excited barks for bones and attention made the skeleton feel overwhelmed enough to excuse himself, promising to come back later.

Promising Grillby. It’d been easy to do and, Sans realised, with very little reluctance on his part.

The fire monster hadn’t said much after that. Grillby only gave him a warm glowing smile as the dogs began listing off their favourite snacks to order. He continued to smile to himself even as his customers seated themselves and he started on the mess of shattered glass.

And a little later on, he’d realise that Sans left the flower behind in the bar.

He hadn’t asked for how long Sans felt this way, so Sans wondered if somehow Grillby had known. Maybe he had all this time, and Sans had been a damned fool for trying to hide it.

Sans grinned to himself as he walked down the street and back to his house, going over the confession in his mind over and over. The twinkling small voice repeated in his head like a hymn, like he’d remembered how to dream after years of nightmares. His soul thrummed behind his rib cage as though he could scarcely believe that it was all real.

And the  _ colour _ Grillby’s fire took on. Its blaze had started out amber and bronze, but then had turned so white with small embers of gold and even tiny flecks of violet and  _ blue. _ Sans hadn’t stuck around long when the dogs came around to see how the bartender would have pardoned them.

Unable to help it, Sans laughed to himself. He didn’t care how he looked to anyone else if he was being watched. He was drenched in alcohol with smears of soot all over his face and hands, burns on his jacket, and he probably smelled like a drunk.

But he was the happiest he’d ever been in a long time and he loved it.

Before he entered the house, Sans took off his hoodie to shake out the remaining glass shards around the side, feeling a brisk chill. Comparatively, he held his jacket close to him with a pause.

Warmth still clung to the fabric, penetrated deep and lingering even then. A little caught off guard, Sans let out another soft laugh. He could detect the scent from Grillby too, the soft hint of charcoal and spice of fire, of hearth and home. Sans felt his soul flush at that and he rounded the side of the house to go inside, resisting the urge to outright hug the garment so he could press the feeling into his bones.

It occurred to him that he hadn’t eaten for most of the day; excited jubilation of his revealed feelings aside, Sans felt hungry. So after depositing his hoodie on the counter, he dug around the ‘food museum’ -- as Papyrus had so aptly named their fridge -- to grab some leftovers.

Sans’ grin dropped a little when he realised it was the previous night’s spaghetti, but that was really all that was left in the house. The taste had been mainly… indescribable, with his limited knowledge of the phenomenon, but Sans just knew that it wasn’t at all pleasant. He was still getting used to tasting things, after all.

Hesitant, but given very little choice in options without cooking something for himself, Sans grabbed a fork from the drawer and leaned against the counter to eat, as usual.

That’s when he realised something peculiar. A click, followed by a jarring grind and he dropped his fork to the dish with a clatter and ran his digits around his teeth. He didn’t feel any cracks, and yet… he could have sworn…

A suspicion along with a nagging worry bothered him enough to walk to the living room with his plate, then upstairs to the washroom. He would just check. It certainly wasn’t anything to panic about. It was probably just a loose tooth from when he fell off the stool at Grillby’s. Sans would simply get Papyrus to inspect and heal it when he got back.

But still… he had to check.

As concern gripped at him, Sans balanced the plate in one hand and scrutinised himself in the bathroom mirror. There was a scuff on the top of his skull where the glass had landed, but other than that, things looked fine. Maybe a smudge of ash from when Grillby got very close, but nothing too out of the ordinary. Puzzled, Sans brought another forkful of noodles to his mouth, eyeing his reflection warily as though he expected something terrible to happen.

Instantly, he felt dread. Unable to help himself, the plate slipped from Sans’ hand and landed into the sink with a loud shatter.

His mandible had  _ opened. _

The forkful of food followed the rest of it into the sink with the screech of metal on porcelain. With a surge of energy, Sans hiked onto his tiptoes, his sockets hollowed and wide as he desperately patted at his face, his mouth, his teeth, trying to find a crack, an injury,  _ anything _ to blame this weird phenomenon on. He searched along his jaw for a hidden crack, something blindingly spreading as he fumbled to get it under control.

His soul jackhammered in his chest, panicked now instead of elated. He didn’t find anything save for a small sliver, a hairline groove that spread from one end to the other.

It had parted.

Despite his shakes, the bone was smooth as Sans traced his finger along the bottom of where his teeth  _ should’ve _ been fused. But they weren’t. They had always been together, so unlike his brother’s, whose teeth could chew, clatter and move as he spoke. They just weren’t, and Sans was beginning to panic more, digits deftly prying in their search for any kind of hint as to  _ why _ as his breaths picked up.

A desperate thought jolted through his mind. Had Grillby’s heat done this?

No, that was asinine to think.

Sans had wondered about his brother’s odd saying: that skeletons were soft and cuddly. He’d always chalked it up to Papyrus’ weird ways with words and how he habitually chose the more awkward path to say something.

Sans squinted --  _ squinted! _ \-- closer, the part of his teeth revealing a second row, and Sans drew back, a cold fear slipping down his spine at the same time. He slapped at his cheeks, his breathing coming in hitched and panicked.

_ What the hell was happening to him!? _

Sans took a moment to recover, turning his face away from the mirror. It took several moments to even breathe properly again. Another thought came to mind that maybe this was another dream. With that, there was a sharp twist in his soul when Sans realised that would’ve meant that he hadn’t confessed his feelings to the fire monster  _ after all. _ That everything leading up to that moment would be false and had never happened.

He clutched at his shirt and shrunk down to the floor, squatting down with a pained exhale.

He didn’t want to think that. It had taken so much to even go back-

No, something else had to have happened. Besides, his face was smudged with ash. Telltale signs that it’d been  _ real. _ Grillby reciprocated and even kissed him-

Sans paused for a moment, heat touching his face as though the fire monster was there with him.

Abruptly, Sans gave his head a shake to dispel that delusion.

He wondered if Papyrus knew; Sans couldn’t ask him now even if he wanted to, not with his cell phone broken. But leaving the house  _ now _ was impossible with how he looked, and using a shortcut when he didn’t know his brother’s exact location was risky. Somehow, Sans felt as though he had very little choice in the matter.

Cautiously, Sans slowly stood up, eyeing his reflection in the mirror. Then, resigned to give in to scientific curiosity, he leaned forward again.

Experimentally, he tugged his mandible down with one of his fingers, another unnerving grind echoing in his skull as the two rows of teeth slid over themselves, finally resting in an overbite when he stopped the movement. Then he pushed his jaw bone up to close it again, his eye lights the size of pinpricks.

_ This felt wrong. _

Sans attempted to clench his jaw together as he’d seen Papyrus do so many times before and flinched at the subtle noise it produced. He certainly hoped it wasn’t anything he’d have to get used to anytime soon.

Sans stood in front of the mirror as he pondered it, then finally worked up the courage to open his mouth without any aid from his fingers. It took awhile, the movement unpractised and foreign, feeling tight where his jaw had become dislocated and connected with his skull. The row of bottom teeth curved inward out of view, unlike his brother’s, his cheekbones a flat mass on either side to hide them.

Then, as his face rested, eye lights still shot and wavering, the seam disappeared and Sans appeared his normal self.

“so weird…” Sans muttered absently, then clapped his hands over his mouth in surprise at the movement.

No, maybe this happened to skeletons, he wondered? And perhaps it was something that happened with him so late since his development -- at least physically -- was stunted in comparison to his younger brother? Exasperated, Sans sighed, his mandible parting with the action. A shudder racked through him at the shoulders with the sensation.

No, this was  _ definitely  _ weird.

Ultimately, Sans decided that he didn’t have time to wait around for Papyrus to get home. He left the broken dish and spaghetti in the sink as he rounded the corner of the hall and thundered downstairs. It was probably the fastest he’d ever moved outside of nightmares. He darted to the kitchen to grab his hoodie and threw it on, then simply teleported out of the house, not caring that he left all the lights on and the bathroom a more than unusual mess.

Sans reappeared seconds later at the entrance to Waterfall, still running before he made another shortcut deeper into the caves.

Bridge seed room -- off he went.

Then again -- wishing room.

Once more -- the glowing river en route to Undyne’s house.

And one more time. He landed with a wheezed huff outside the river person’s ferry stop, slightly off-kilter as his feet trained on the mossy ground.

Sans bent over to calm down, his soul shuddering in achy protest as he took a few moments for the wave of dizziness to pass. Usually he concentrated when he took successive shortcuts, but this time Sans’ mind was all over the place, and thus so was his aim.

As casually as he could muster, he strolled down the corridor and up to the old turtle’s shop. Apprehensive, Sans idled in front of the hole carved out like a door, then knocked against the old rock surface. Sans had one hand covering his teeth as his eye lights darted around the shop, picking out a few items here and there before they settled on the ancient thick-skinned turtle.

Old Gerson was the oldest monster in their neck of the Underground, old enough to have lived and fought in the war against humans it was said, centuries past. He’d been the legendary Hammer of Justice, a nomenclature Undyne was inspired to take up to honour his bravery, or something like that. Now he was a shopkeeper and excavator of sorts, shuffling through letters he forwarded to Snowdin and who’d sell ‘neat junk’ that he found on his strolls through Waterfall to anyone that passed through.

So when Sans turned up without his brother, the old turtle guffawed, never serious when speaking to either of the skeletons.

“y’know, i, uh-” Sans had to stop himself, his mandible biting on every word. He would have to keep himself in check until this was sorted out, he realised in a barely restrained panic.

“Whoa there!” Gerson greeted, his worn feet shuffling against the ground below in a spunky swagger. “Been awhile, wahah! Papyrus’ brother, right?”

Dumbly, Sans nodded, still covering his teeth. His eye lights were still small, on the verge of guttering out so no one could see how petrified he was.

“i, uh, i got questions? about… skeletons. if you’re not busy? heh,” Sans tried speaking calmly, but his soul thrummed with dread and terror, and his voice sounded strained.

“C’mon in, kiddo, take up a chair. We’ll have ourselves a chat,” Gerson replied, his voice croaky yet loud and gritty. He fixed his good eye on Sans’ skull as the skeleton passed inside to sit on one of a few old lawn chairs that had been fixed with a bent coat hanger. “Questions about skeletons, eh? Been awhile, yes, a long time since then, I suppose. Anything you wanna know in particular?”

“uh,” Sans started, not really knowing what to say. “i guess… you tell me, pops?” He removed his hand from his face and gave his teeth a few embarrassing clacks when his jaw moved up and down. Then he gave a half-hearted and shamed shrug.

“Eh? Isn’t this something you should be asking your parents about?”

The turtle took a seat across from him on a sturdy-looking bench that supported his weight and thick shell. His single yellow eye remained fixed on the skeleton and he leaned closer, head cocked to one side as though it made it easier to listen.

Sans took a breath as though to answer that, but he found that he really didn’t have an excuse. To his recollection, it had always just been him and Papyrus. In fact, he couldn’t really remember if they were raised with guardians or not, come to think of it…

“no parents. no other skeletons in the capital either, so, uh… i gotta go off your memory, if that’s ok.”

Gerson’s good-natured laugh made him smile a little uneasily. Normally Sans wasn’t the one to ask him questions; it had always been Papyrus’ blistering curiosity that allowed him to drill the old turtle with reckless abandon. Sans was the reserved one of the two, after all. Either reserved or moody.

“It really should’ve been something you’d been taught in your stripes,” the old monster responded, but in his voice there was a subtle jab at him. “Unless you’re just wearing big boy clothes to hide you’re still a kid yourself! Wah ha ha!”

Sans felt himself frown defensively at that, the feeling of the downward tug strange, but definitely recognisable. He definitely wasn’t a kid anymore, even if half the offspring in Snowdin outgrew Sans on a yearly basis.

“Well, maybe not so much anymore! Hah!”

Sans bristled at that, already regretting coming here in a panic. But he huffed out a patient sigh and decided he might as well, since he was already here.

The conversation had been long -- too long. Sans feared that if it had taken any longer, Papyrus would be calling the entire Underground to look for him. He’d learned a lot; mainly, that the old turtle was  _ ancient, _ and with it came the susceptibility that the older a monster was, the more memories they hung onto. And with the plethora of knowledge or memories came mixed information.

Gerson didn’t remember a lot from his time with any skeletons, but the information Sans was rewarded with for his patience was enough to go on for now.

Skeletons, from what the old monster recalled, could have ‘frozen’ expressions, pliable, or a mix of the two. Papyrus was a prime example of pliable, and Sans was evidently a mix. It would change dynamics as a skeleton approached maturation, of when either stripes were shed or when the skeleton was ready for more intimate relationships with a mate.

Or, in layman’s terms… dating.

Tastes were a way of signalling a skeleton’s body that these changes were taking place, since there was little else to change with bone structure. Maybe physical density was affected? Magic surges? He wasn’t sure. There were apparently other signals, but Old Gerson seemed to have conveniently forgotten them.

The way the old turtle explained had been scholarly and condescending, but at the same time Sans couldn’t help but be starkly embarrassed by the entire conversation. He spent the majority of the time cowering with his face buried in his hands.

Sans had always been smaller than the general populace, maybe a head or two shorter than most adults of similar makeup to him. But to think he was so late in maturing that Gerson felt the need to crack jokes at his expense. He felt embarrassed and flushed, but it would explain so much, especially since the experimental treatment he endured as a child-

_ Don’t think about that- _

Like a switch flipping from a horror show to an educational tutelage, Sans pushed the last thought away. While he knew about all manners of other things, biology was admittedly not his strong suit. It’d be something to talk with Alphys about. She knew a good deal more than he did, even if she specialised in robotics.

Sans decided to walk home instead of teleport. The ferry wasn’t idling where it normally was and he felt exhausted from the emotions of the day; so much, he didn’t realise a voice calling after him until they’d caught and yanked on his hood.

Jerked back, Sans whirled on the spot, nearly losing his balance. His magic flared in a defensive spurt and he caught himself as he was met eye to eye with the resident fish lady. Her sharp teeth gleamed with the glow of illuminated water around them in something that could only be described as a snarl, the gills of her neck flaring.

Sans withdrew his magic and went to offer a nonchalant greeting, but he was cut off by Undyne’s raucous voice.

“Sans! I’ve been trying to contact you for DAYS!!! What gives!”

“my phone’s no longer of this world,” he drawled without missing a beat and feigned utmost sorrow almost theatrically. “no longer do i hear its sweet cries during the night-”

“Cut the crap, boney boy! You missed-” Undyne counted off on her scarred, webbed fingers, “four shifts in Hotland since Papyrus told me about that!”

“hotland bites,” he tried again, citing Undyne’s sentiments for the sweltering quarry perfectly.

“It SUCKS!!”

“i had an… escort mission, kinda. had to, uh, get cover. on short-notice,” the skeleton replied lamely, avoiding her look as thoughts of his time with Grillby snuck up on him. It  _ had _ been an unofficial leave, after all.

She stared at him plainly, then just shook her head with a frustrated snarl. “You could’ve stopped by on the way!” Her tone was bitingly accusatory and concerned. “What if something happened? What if a HUMAN showed up?”

“i don’t think they’d make it that far past the canine unit. papyrus can hold his own, too, at least ‘til you showed up. besides, we kinda sidestepped this area, going through,” Sans explained carefully; he knew that he was treading on thin ice with Undyne enough as it is. “anyway, what’s up? can it wait until morning? i’m kinda tired and i still got a long walk.”

She leaned in close to him suspiciously and sniffed, the slits in her face flaring in disgust when she detected the burn of alcohol on Sans’ hoodie.

“Have you been DRINKING!?”

“nah. long story. still  _ reeling _ from it.”

Her eye flattened at the poor attempt at a joke and he shrugged. “Fine! I got a few messages from Alphys in the lab and she wants to talk to you,” she groused, but her glance softened and skewed to one side as Undyne mentioned her name. “Said to come as soon as you got the message. Something about weird ‘readings’.”

Sans shuffled his shoes on the ground, tapping the toe idly with a distasteful grunt. “what,  _ now?” _

“Or tomorrow! Whatever. She said she’s been digging into it for the last couple weeks and wants your opinion on something. Maybe bring your phone so she can fix it. She’s awesome at that!” Her eye narrowed as she regarded his face with scrutiny, noticing the shift of expression. “Erm…?”

“since you’re so concerned about missed shifts,” he drawled, scratching at his nasal cavity with feigned disinterest and pointedly ignoring her look. It may have been to hide the fact he could feel his teeth moving, still. “why not ask my bro?”

She paused, eye widened at the prospect, then her expression shifted into a bizarre mix of uneasiness and gutsy bravado. “You know I can’t do that…”

“and why not? it’s all he ever talks about. royal guard this, training that…” Sans huffed and gave her a wink, “ok well, maybe not officially. maybe like a temp? just ‘til i get back. he’ll be good. scout’s honour.”

Undyne growled under her breath as though the decision being made then was a bad idea. She stared him down, as though she was mentally weighing the pros and cons of the entire situation and how it would play out in the future.

Then, finally, she relented; “I guess as long as it’s temporary-”

“sure.”

“I just don’t want him to get hurt, y’know? Guy’s got spunk, but… I dunno,” she snarled indecisively again and shrugged, her gills flaring at her neck again. “I guess! Whatever!! Temporary shifts, just this one time -- seeing as he’s already done it  _ for _ you. As a favour to Alphys, since you being there would help her out.”

“ok,” Sans automatically replied through a sigh. Admittedly, he was just grateful the renowned Spear of Justice didn’t press her curiosity of his new ‘look’. He watched as Undyne stalked off in the direction of her house, shaking her head as she went. Then she rounded to face him again and pointed at him with a heroic flair.

“Oh yeah!! She said bring your old notes!”

Sans paused with the addition. Then he realised that other than Alphys, no one else really knew the details of his assistant work at the lab in Hotland -- and sequentially, the CORE. The built up tension in his body slowly drained away and he let out an inaudible sigh of relief.

Shrugging, he replied, “ok.”


	2. Chapter 2

**Summary for the Chapter:**

> Sans gets so wound up after trying to ask Grillby out that he shortcuts into uncharted territory, skipping his cardinal rule. Alphys is puzzled over the negative photon readings her radar is spewing out, and discovers Sans’ maturation, much to his discomfort.

He didn’t want to, but Sans forced himself. In fact, in order to ensure that he’d be well-rested, Sans retired as soon as he got home after mumbling to Papyrus to wake him a little earlier than usual. This was of course after his brother’s predictable overreaction to his mandible, a bit of reheated supper, and Papyrus’ disgust at the whiskey-soaked hoodie.

Papyrus made a big show about the state of his clothes, which had been rendered to a sooty mess, singed patches and fur. Then he gave a suspicious glance Sans’ way, ending up looking fairly smug about something. Sans decided to ignore the look, feeling his soul flood with the memory of what happened at the bar.

Reluctantly and not without an extended argument, Sans surrendered his clothes so that they could be properly laundered. Something inside of him twinged when he realised a little too late that the scent from Grillby’s would be lost in the wash.

The brief checkup Papyrus subjected him to was painful, to say the least. The barrage of questions and banter back and forth about the mess in the washroom, along with the discovery of Sans’ unfused mandible was admittedly, a weary interaction. It took far longer for Papyrus to be satisfied that Sans truly hadn’t injured himself, but he had a bunch of questions that Sans felt he just couldn’t answer. At least, not immediately; he felt far too embarrassed and ashamed for even the most cursory of explanations.

So even after he evaded the questions about his evening, Sans retired to his bedroom and quietly closed the door. It felt like ages since he’d been there last; every dirty sock was in its same place, the whirling dervish as whimsically pointless as ever… The only difference now was that Papyrus had put his slippers in his room, just next to his dresser.

It felt so long since he’d slept in his own bed. The day had been long and tiring and he’d gotten back late. It had been so full of emotion, of fears Sans thought he’d never confront. The interrogation had eaten up a few hours as well. He barely had the energy to kick off his shoes, but he managed to before sinking back against the bare mattress. Without his hoodie, he definitely could see the glow under his shirt, subtle yet there.

Sans’ grin tugged slightly at the memory of the lulling heat against his sternum and sat up to summon his soul. It was small, more fragile and paler than it used to be. As always, there were small, barely visible stress marks, like scars. It wasn’t what he was focused on, as much as it discomforted him to have it out in the first place.

However uneasy he felt, the glow it produced every time Sans thought of his friend soothed him. It pulsed radiantly with his growing sentiments and Sans pressed it back to his breastbone, returning it home where it could safely rest.

He’d have to remember to visit the bar in the morning before he left. With pleasant feelings nestled inside, the skeleton actually slept deeply and well.

True to form, his brother woke him with the first light, brandishing his freshly laundered hoodie. Sans groaned sleepily as the garment was flung on top of him. Absently, he pawed at the air when Papyrus opened the window to let the first beams of magical dawn hit over Sans’ head.

“five-mur-mins…”

“SANS, YOU LAZYBONES!! GET UP.”

“dun wanna go to school…”

“OH, FOR STARS-… SANS, PLEASE. YOU’VE BEEN OUT OF SCHOOL FOR 97 YEARS. YOU REQUESTED FOR ME TO WAKE YOU. SO THAT IS WHAT I, YOUR BROTHER, AM GOING TO DO! AND AM NOW PRESENTLY DOING!!”

The smaller skeleton groaned as though in pain, knowing it to be true. Why did he do this to himself? After a moment of sleepy consideration, Sans heaved himself up off the mattress, his clothes rumpled and mind barely registering as awake.

“m’up.”

“YOU KNOW…” Papyrus moved to sit beside his brother on the bed and patted his shoulder. Perhaps a little rougher than warranted, but he wanted to ensure Sans would stay awake. “THIS HAS PROBABLY BEEN THE LONGEST YOU’VE EVER WENT WITHOUT BAD DREAMS?”

Sans dozed on the spot, then tilted his head back to rouse himself. His posture remained slouched with his hoodie hanging off one of his arms. Cradling his chin in one hand, Sans hummed softly.

“that so..?”

“YES. RIGHTLY SO! OR, AT THE VERY LEAST, YOU HAVEN’T BEEN COMPLAINING ABOUT THEM!! WHICH MEANS, I HOPE, THAT THEY’VE BEEN ABSENT!! AND IT’S GREAT TO HEAR! I COULD NOT BE MORE RELIEVED! I HAVE BREAKFAST ON DOWNSTAIRS. SO HURRY UP AND GET READY.”

“ok.”

“SANS! I SAID WAKE UP!!”

When Sans finally pulled himself out of bed, it was done groggily and as if on automatic. Every movement was a chore as he shifted his feet into the slippers by his bed and he pulled on his hoodie, leaving it open for once. It slouched off his shoulders as Sans dragged himself downstairs, bones creaking and protesting with every step. Once he reached the kitchen, Sans was pulled from the doorway to his usual seat and forcibly sat down, still half-asleep.

Though Papyrus was typically an early-riser, that morning he seemed more energetic than usual. Sans regarded him in his drowsy stupor and finally yawned, his jawbone doing that odd little  _ click _ with the unpractised movement and he arched his spine with a series of pops and satisfying snaps.

“sup, bro.”

It took all of three seconds for his younger brother to exclaim excitedly, slamming his fists down on the kitchen table and making the silverware rattle in the bowls. Sans didn’t jump, but he cracked open an eye with the reaction.

“UNDYNE! SHE CALLED ME!! I, THE GREAT PAPYRUS, AM NOW AN UNOFFICIAL, TEMPORARY, HONORARY SENTRY… OFFICIALLY!!”

Sans grinned, slumping onto the table. Go figure that Papyrus would get so excited over something as trivial as a cover shift; one orchestrated by Sans, since Undyne hadn’t exactly granted him official leave. Still, it wasn’t as though anything would happen. Sans didn’t have the same eerie premonitions lately that he had weeks ago. He supposed it had probably been his depressive mood that affected him.

Regardless of his thoughts, Sans made an effort to send a supportive yet sleepy grin at Papyrus.

“congrats, bro. where’s your station?”

“SNOWDIN FOREST! NATURALLY, SINCE I’M SO COOL.”

“of course.  _ snow _ where better suited for you. you’re the best for the job,” Sans agreed candidly as he pushed himself from off the table. “my cool bro, you’ve done it. i’m super prouda ya.”

“FINALLY, SOME RECOGNITION…” His brother theatrically imposed a fist to the ceiling, cackling with glee. “PERHAPS -- DARE I SAY IT -- IT WILL BE THE DAY A HUMAN ARRIVES!”

“that’d be right up your alley,” Sans replied with another yawn. Then with a bit of an internal struggle, he looked down to the noodly breakfast his brother had lovingly concocted.

Throughout breakfast, Papyrus made subtle jabs at his eating habits, urging Sans along and giving humorous demonstrations with his oatmeal on how to properly chew with teeth. Sans felt more than a little injured at the infantile way his brother was treating him, but he wouldn’t have to deal with it for long. Soon, Sans left the house with a rucksack full of his old notes, some snacks, and his broken cell phone.

Admittedly, he was hesitant to go to Grillby’s in the morning. Usually the bar was closed this early, but Sans had a feeling that he couldn’t just leave for a few days without trying to say  _ something. _ So, despite being anxious with everything, Sans approached the door to Grillby’s, finding it locked. It took an insurmountable amount of time for him to finally get a hold of himself enough to bring up his hand and rap his fist on the frame.

He noticed how stupidly nervous he’d become during the wait and idly shuffled on the spot. Sans had opted to keep to his slippers from now on; the shoes were nice, but he preferred to be comfortable. The slippers provided that satisfying squish in the snow wherever he stood.

He waited a while longer until he realised that there wouldn’t be an answer to the door at this ungodly hour. His soul gave in to a harsh, dejected little thud and Sans turned his back to the door. It was just as well, since he didn’t quite know what to say to Grillby in the end.

That’s when he heard the door open, the subtle jingle of chimes sounding clamorous in the early morning. The fire monster came into view and peered from around the door, something in his expression shifting from groggy to rapt when he saw Sans. For a moment his flames seemed to arrange into a warm greeting, his mouth parted in a glowing smile that reached his bright eyes.

Grillby didn’t utter a word, but he silently watched as Sans stared and then stumbled over the beginning of several sentences like a precious fool.

“i’m, uh,” Sans started, idly digging into one pocket with one hand while he shouldered his bag with the other. It took a conscious effort to keep his mandible carefully closed while he spoke, so much that it distracted him from arranging his thoughts. “i’m… i’m gonna be gone for a few days. i just wanna… wanted to say. i mean,” he faltered, eye lights settling on the fire monster’s face, then down to Grillby’s mouth. Abruptly, he tore away his gaze, remembering the intimate moment they’d shared the previous evening, the thought loud and intrusive in his head.

_ “Didn’t realise that… you were so articulate in the morning,” _ Grillby breathed, a hint of a tease in his voice as he pulled open the door wider to lean against the frame.

Sans felt embarrassment flood through his body at that. Grinning awkwardly, he pulled the hood of his jacket a little over his eyes when his soul started to thunder wildly.

“…maybe, when i get back… me n’you-” He mumbled the trail end of his thoughts into something hopelessly inaudible.

Grillby stayed silent, although his demeanour shifted in subtle surprise at the implication. Sans peeked from under his hood and caught the way the flames at the bartender’s face fluttered a soft gold. He felt a little more nervous, if that was even possible.

“when i get back…” the skeleton started again, his courage tentatively building. “we… i mean-” He stopped, realising how flushed he felt and how Grillby’s smile had spread the more he spoke. “…maybe…”

He let the sentence hang; he couldn’t do it. Sans was pretty positive that if he pushed himself a little more, his soul would just shudder and come to an abrupt stop.

Despite himself, Grillby couldn’t help but grin more as he watched the way Sans shuffled from one foot to the other. He liked the way Sans was flustered and how he hid and bashfully grinned to himself. That was perhaps the reason why Grillby chose to lean forward, boldly taking hold of the hoodie’s drawstrings with one hand and pulling him closer, leading Sans so he could whisper against the side of his skull.

Before he did so, Grillby paused, his smile curling with delight when he began to hear the subtle clatter of bones and a startled inhale. Excitedly, his flames fluttered against Sans, the fire monster’s soul trembling in response.

Then he murmured, a breath’s sigh away from Sans’ face;  _ “Take your time, Sans.” _

It was as much as Sans could handle. Before he could get another stuttered word out and only after Grillby had let go of the drawstrings, Sans fled. He didn’t even know exactly why, apart from being so hopelessly worked up by the gesture that his magic immediately pooled inside of his rib cage and itched to break out.

Without thinking, he’d teleported away, leaving the fire monster to quietly laugh in triumph. He rather liked that reaction, although he speculated that he’d likely have to coax Sans into staying longer next time.

It took Sans several moments to calm down, his soul fluttering and his face beaming. After he was able to think straight, he then attempted to figure out where he was.

Though starts and stops were important, he’d broken his cardinal rule and acted out of impulse. Now he wasn’t quite sure where he’d ended up. Apart from a bare knoll that stretched on for several yards, it was significantly darker than what was normal. Even though the cave’s glistening walls were faintly illuminated by small glowing mushroom caps and gnats, a pressing darkness seemed to seep down from the ceiling to coat everything around him.

The clearing beyond was a little out of place, a dull glow drifting up from his feet. Sans groped around in the darkness until he was able to regain his bearings, the cool humidity of the corridor conflicting with the gentle ache of warmth in his face.

Sans looked around, his soul still thundering wildly with Grillby’s tease, though he felt like something wasn’t right.

He didn’t know where this was. The cave system  _ looked _ like Waterfall. The plants were the same. The echoing sighs of water that sloshed in the distance were familiar enough, yet something gave Sans the impression that he wasn’t supposed to be here.

Uncomfortable, Sans shouldered his bag, his eye lights scanning the corridor as the flustered feeling in his soul melted away into a lingering, familiar malaise. He attempted to collect himself, to gather an influx of magic so he could attempt another shortcut.

The same creeping sensation rocked into him, the same as he’d felt at the CORE. Much to his confusion, his attempt faltered again, magic fizzing and sputtering out like a flame in a gust of wind.

A sudden chill slipped down his spine and Sans shuddered, warily looking around. It was peculiar, but it didn’t quite feel cold either; a better term for it would’ve been the exact polar opposite to heat. His legs felt weakened as though strained, but he pushed himself to walk down the corridor.

Unless he could figure out where he was, Sans doubted that he’d be able to continue. It twisted a horrible thread of dread into his mind, one that extinguished any lingering heat and happiness that he’d experienced earlier.

What exactly was this place?

He had to be walking for what felt like hours. Unable to repress it, Sans had begun to shake. His breaths were hitched between gasps and he started to panic the longer he couldn’t find his way. His footsteps were uneven as his hand brushed against the corridor’s walls, the familiar glide and jutt of ore and crystals grounding him as he passed. The sound of water in the distance steadily became quieter the more he walked, signalling that Sans had been wandering further away from the starting point.

Waterfall always had water. It was its namesake, so when he couldn’t hear it anymore, something clicked in his skull. Like a light that went off and he was surrounded by darkness.

Eventually, Sans stopped, his bones having rattled the entire way. He felt exhaustion sink into his body, enough that he couldn’t push himself any further. Giving in, needing a sound, a noise, a shape in front of him, Sans sat against the wall. He slipped the rest of the way down, drew up his knees against his chest and bowed his skull into his arms with a strangled swear.

The darkness was closing in.

“just… just a bad dream,” he breathed softly, trying to fill himself with confidence and not the overwhelming anxiety pressing inward from all around him. “c’mon, sans. pull yourself together.”

He hated the way he was becoming unravelled over a bit of darkness and unfamiliarity, but this was nothing like his normal Waterfall. In all the time he’d spent here, Sans hadn’t heard even a  _ whisper _ of any other soul. There weren’t any echoes from flowers that normally littered Waterfall.

It was like the place was dead.

After a few moments, Sans blindingly picked through his bag. Papyrus had packed him some snacks, wrapped in kerchiefs and napkins with a pattern he couldn’t quite make out, even with the glow of his magic. Although his brother seemed to enjoy giving him nothing but pasta lately, Sans was relieved to find some kind of granola slab. It wasn’t unpleasant, but he couldn’t understand the taste with what limited experience he had with the new sensation. He just hoped it was enough to get him through whatever was happening.

After his admittedly nerve wracking meal, Sans pushed himself up and turned around. He couldn’t shake the feeling of something lingering close by, of the clearcut dread that persisted him as he walked. Unable to help himself, Sans’ steps became faster as the sensation pressed against him from all sides. To keep them from chattering from the dark and the cold, Sans clenched his teeth, his soul’s magic twisting and flicking subtle shades of cyan around him.

Despite his agitation, it helped to illuminate the path. The corridor was familiar and yet not, but as he continued on, something in the distance caught his attention. The closer he got to it, the more hesitant he grew, finally realising what it was.

A door.

A simple, granite door that looked as though it was sealed shut. Old and dead moss covered the seams and everything in his body screamed at him to run away. Yet at the same time as he approached it, Sans couldn’t help the overpowering urge to go for the doorknob.

He resisted, the sensation conflicting with his innermost desires. But he should open it.  _ Had to, _ even. He had to run. Whatever was beyond the door pulled at his existence like something lost, wanting to be found.

He didn’t want to. He wanted to  _ run. _

But… he had to open the door.

_ “stars help me,” _ Sans shakily whispered even as he leaned forward.

His eye lights shrank to pinpricks as tension flooded over him; he felt like he couldn’t control himself. His phalanges trembled as they reached for the knob. The old worn metal was again oddly familiar as his bones grazed against its surface.

A warbling noise was echoing from beyond the door and Sans felt an immediate sickness as something akin to static electricity filled the air, heavy and hard. His magic continued to arc and erratically bubble around him, throwing gold and cyan against the grey door in a flicker of terrified, uncontrolled surges. He stared in horror as his fingers clasped over the door knob and when his wrist turned slowly, Sans felt a scream lodge itself, stuck in his chest.

He shook, every bone in his body trembling as the door swung inward without a sound. The disgusting noise of what he could only imagine  _ had _ to be thousands of warped, twisted and imploring voices continued, sending another chill through him.

Finally, he was able to withdraw his hand. Immediately it went to his chest, shoulders hunched up in fear as his wide eyes sought out anything in the darkness. The glow from his magic was engulfed by whatever was behind the door like a black hole, as though an insatiable thirst longed to pluck every speck of light from the area.

The feeling that something or someone was watching him persisted, and Sans took a fearful step back, away from the door. His magic twisted painfully along his spine and he couldn’t help the strangled gasp that escaped him as he took another step backward. It creaked up his back, forcing him forward, urging and repugnant. A tightness welled up inside of him when he tried to resist, a thousand plying fingers pushing him forward.

Cautiously, he allowed himself a step forward. The pain subsided by a substantial amount, though it wasn’t what Sans had wanted at all. He chanced a glance behind him, but he couldn’t see anything.

It seemed like going forward was the only option.

Inhaling another shuddering breath, Sans stepped forward once more. His arm reached out in front of him to brace against the open door. As soon as his fingers brushed the old granite surface, he felt his soul give a sickening lurch.

He hunched over, dizziness flooding his senses, pouring out of his eye sockets like black ink. It brought him down to his knees and he panted, something welling up in his mouth. Desperately, he braced himself against the frame of the door as it swung open, without a single creak to break the silence, Sans could only feel nauseated with the sensation.

「  ░░░░░░░░░░░░░░░░░░░

░ ▓▙▛▓▌▞▟▓▓▚▖▉░▙▀▖▉ ░

░░░░░ ・░ ・░・ ░ � ░░░

░░░░░░░░░░░░░░░░░░░  」

Wildly, Sans stared into the unforgiving darkness, the cut of voices sudden and shrill with no sound of an echo. His magic’s light had been snuffed out and he couldn’t see a thing, but the sudden scrape of static filled the inside of his skull.

His hands abruptly flew to each side of his head as the long tendrils of scattered sound etched into the innermost sides of his mind. More pain welled up inside of him, blinding and black as his scream was choked off.

_ Fall. Lost. Found. _

_ Bid. Curl. Meld. _

_ Absorb. Bone. Break. _

_ Consume.  _

Sans inhaled sharply, willing everything in him to  _ move. _ It took everything he had to vault to his feet again, blindly turning back into what he prayed was the exit. The overwhelming ache in his soul pinched at him, extracting a pained shudder and fearful whimper from Sans. As fast as his legs could carry him, he located the door and passed through.

Then he dropped out of the dark room that threatened to swallow him whole.

In an instant, he landed in a trembling heap; every fibre of him felt suffocated. At some point, he must’ve covered his eyes with his hands, the haunting burn of a scored white face in the shadows of his skull accompanied by the haunting key of static.

Sans trembled, silent, bones clattering together in a twisted, ugly symphony of terror and utmost revulsion. He couldn’t help it. He just sank lower and lower, inching to the cold moist ground with a shuddered cough, his breaths catching on every exhale.

Thankfully, the infinite darkness stayed behind the door.

Eventually it became easier to breathe and when he brought his sleeve up to wipe over his eyes, they were dry. His magic manifested in a rush like a bursting dam and he clutched at his bag in a deathlike grip, very clearly envisioning where he wanted to go. If he could, Sans didn’t want to appear anywhere in Waterfall anymore.

No, he’d had enough.

It took awhile to find a fissure in reality, for Sans to run the fingers of his mind over the seamless landscape around him in his desperation to flee. It took so long that he’d started to doubt if this really  _ was _ reality.

Choking noiselessly and trembling, Sans dragged himself to the opposite side of the corridor to calm down, furthest from the door. As it became easier to get a hold of himself, Sans finally found a crack to exploit and stumbled through, his slippers landing clumsily in the red, dusty earth.

Uneasily, he waited next to a gurgling ravine. One eye hesitantly cracked open, afraid of what he’d find. With a surge of relief, Sans recognised the ferry stop and the area surrounding it. He huffed loudly and leaned back against the quarry wall, all the anxiousness and fear flooding out of him in a powerful crash. He shrank down against the wall to sit, using its solidity as an anchor. Suddenly every particle that composed him felt weakened, the adrenaline finally running dry.

He’d rest there. Get his bearings again. He pulled his knees towards his chest and buried his skull in his arms, soaking in the glow of the lava floes and the heavy sounds of magma. Somewhere in the distance, he could hear the chatter from random passersby.

_ What the hell was that? _

At some point, Sans had succumbed to exhaustion. He awoke some time later, disorientated and sore, but at least it was still in Hotland. The rolling heat from being so close to the earth’s core made him feel a little better. It reminded him of his friend, and he was almost loath to leave it as he headed towards the lab, where it was likely to be air conditioned.

It appeared that it was either too early for him to be expected, or the royal scientist was enraptured in cartoons again. Expectantly, Sans stood outside the large building and stared up at one of the cameras posted on the building, aimed down to where he waited. A little curiously, Sans noticed that the red LED indicator wasn’t lit and idly wondered if it was broken.

Tired of waiting, he released a heavy sigh and rapped his bony digits against the metal door.

Several moments passed and Sans began to grow restless, but he didn’t want to attempt using a shortcut again. He was still rattled from the earlier encounter, not fully understanding it. Maybe it was something that Alphys could help him figure out?

Even more time passed and while Sans found he now liked the heat, he disliked standing for very long. Even though he’d napped, he didn’t feel truly rested. He still felt on edge. The words that had chanted in his head didn’t make sense, so he went over them in his mind, repeating them like an odd jumble solution.

_ Fall. Lost. Found… _

Then a recollection; that cracked face. He thought he’d seen it before, but it was as mysterious and foreboding as the area that he’d been trapped in. He couldn’t connect any memories in his past as to  _ why _ it was familiar, though.

Maybe it was better if he didn’t try to.

Sans didn’t like the implication that his mind was trying to wrestle the thought that he knew of it, or had at one time. It was both familiar, yet hauntingly foreign. As he waited, he parsed his memory for the vague disturbing smile, coming up blank.

Sans soon grew agitated enough to rap his fingers against the solid steel door once more, this time hearing the approaching flurry of footsteps and a voice echo from just inside. With the hiss of mechanics and the door finally opened, Sans stepped inside, giving his buddy an uneasy, wide grin.

“heya, alph. long time.”

“Sure… has,” she replied, matching the discomfort more readily than Sans ever could. “Made the trip ok?”

“piece ‘o cake,” Sans lied automatically as he followed his former colleague through the hall to the computer room. There wasn’t any reason to delve into his anxiety so quickly, and he needed somewhere secluded to rest.

It was just as he remembered… well, maybe not. In truth, it was a hell of a lot messier than he last recalled, not that he minded. Needing a distraction from the chilling experience, Sans turned to face her.

“so what’s the hubbub, bub?”

Alphys started to speak, the sentence then aborted. She tried again, her claws nervously skittering over each other. Sans didn’t point it out, but she seemed more agitated than usual. He approached the other side of the workspace and set his bag down with his notes, then sat on the floor next to it, content to rest for awhile in a place he considered safe.

“must’ve been important, to get fishie to order me here.”

“U-Undyne,” Alphys corrected, then she took the chair next to him from in front of the large computer screen. Papers were scattered everywhere; maps, blueprints and graphs made a haphazard blanket across the floor in seemingly unorganised piles. “And… and yes, there might have been a, uh. An… eensie tiny little problem?”

“like what.”

“Your… your security code, a couple weeks ago,” she replied, flipping through a few stray papers that had red circles drawn over it. “h-here-” She handed them over for Sans to parse through with a frown. “I mean, you worked there! At the Central Origins Resource-”

“just say ‘core’, alph. no one calls it that anymore,” Sans interrupted, pouring over the graphs.

She stopped abruptly, clearly avoidant, but she stared openly at him. Sans was used to getting the odd look here and there, and he tried to ignore it. The girl was in fact one of the reasons why he was so late in maturing, and the entire reason that he still existed, for that matter.

Uncomfortable as his mind threw up cyan, yellow and a flash of white, Sans rubbed at his face. “what’s up.”

“When… when did you-?”

She gasped, as though whatever had passed through her head was either scandalised or a earth-shattering breakthrough. Sans shrank down, dismissing the reaction and tapping on the graph with a single digit. It was a gridline layout of Waterfall, and on another larger paper, the CORE. Certain areas were circled in red marker and he could reckon what they were immediately. The Waterfall ones, anyway.

“i had to move around a bit. had a tag-along,” he evasively explained and took a moment to scratch the side of his head. Then he felt the tentative, curious prying poke of magic against his soul. Scandalised and aggravated by the Check, Sans whirled his head around to shoot a pointed glare Alphys’ way. In response, she looked at him sheepishly. “do you  _ mind?” _

Her laugh was excusing, yet still nervous. She was the only one who he’d allowed to Check him, but only since she was one of the very few who knew about his low HP. She also was more than aware of the circumstances of his soul, since it’d taken a nosedive ages ago.

More patiently than he would’ve been in the past, Sans sighed in resignation, burying his chin in one hand.

“so… everything in order?”

“You’re… h-healthy!” Alphys reported a little too eagerly. Something in her eyes just didn’t match up, though.

Sans looked inward at the singular digit and hid a grimace. It was lower than before; that…  _ thing, _ whatever it was, had lowered his resistance and shaved him back down to his singular HP.

“No, I mean… after you quit, you stop.. stopped coming around, so I, um-” She stopped and tapped her claws together, going over what she wanted to say in her mind. “I never really knew if you were… you know. Ok?”

“the only reason i’m here is ‘cause of you.” Sans shrugged, a twinge like a shot from the memory bruising inside of him -- or what remained of it. “don’t think too much about it, alph. i don’t. i just hate travelling and i like to complain. so, about this stuff-”

He pointed to the graphs and grids as he started to explain what had led to the analmolic reports, without mentioning just  _ who _ had tagged along. Sans was acutely aware of Alphys’ staring whenever he spoke and the way her eyes would catch his movements. Scientific curiosity and friendly excitement was a dangerous combination.

As he reasoned through it, Sans noticed that a circle corresponded with every time he had to warp with Grillby. Every time, except at the CORE, where he’d first felt something. Something he could only describe as a hiccup.

Conveniently, Sans decided to leave that part out; additionally, Alphys seemed more of an anxious wreck than usual, and telling her about the strange area in Waterfall would just make her more nervous. At least, he reasoned, not now. He needed to figure it out for himself before he made Alphys worry or panic.

After a while, they both poured over the combined research papers and after hours passed, gradually Sans introduced his old notes too.

“O-oh!” Alphys exclaimed as she picked up a paper that admittedly looked as though it’d been balled up and smoothed out about forty times or so. “Wow, that’s… it’s been awhile since I’ve had to read cipher!”

“lemme see.” Sans gestured for the paper and squinted at it. “oh. wow, me too. what is this, college stuff?” Bemused, he scratched his jaw again as he read over the paper, not making sense of the odd symbols that were scrawled across it. Alphys stared at him again and Sans caught it. He caught the look and sighed in resignation. “welp. you might as well go ahead and ask, buddy.”

A flush of crimson spread across Alphys’ face and she awkwardly gestured to, well, all of him. Sans lofted a brow ridge, then grew conscious of the movement and clapped a hand over his face, exasperated.

“seems when you said the, uh, treatment… delayed some stuff? maybe it wasn’t as permanent as we thought. and maybe that stuff is coming up now.”

“I knew that!” she huffed and rocked back on the chair, her tail flicking thoughtfully. “I could have… told you that.”

“if i’d come back. yeah, i  _ know.” _ Idly, Sans tapped a pen against his teeth, then opened the part to test the lid between them. It was still weird.

“From… from a purely scientific standpoint-”

Sans paused and his eye lights dragged over to watch Alphys as she spoke.

“Do you think… do you think maybe…?” She grinned and spread her claws out questioningly, to the area where all monsters housed their souls, his chest. His eye lights fixed on them, hesitant.

“oh.”

Sans let the pen drop from his mouth and he sighed. She was right; it  _ was _ something he’d been avoiding. But, if there was anyone he could trust most, it was definitely Alphys.

As uncomfortable as it was for him to be so open with his fragile soul, Sans pulled down the toggle of his hoodie and shrugged off one sleeve. Then, a little self-conscious and wary, Sans coaxed it out of hiding.

“it didn’t change much since the last you’ve seen it, i guess.”

Her eyes glinting, Alphys suddenly straightened in her chair. Her glasses nearly tumbled from her snout and her toothy grin was wide as she released a nasally cackle.

“Are… are you kidding!! Look at it! It’s…” She trailed off, but she couldn’t repress the reverence and excitement in her voice even as Sans gave her an inquisitive look. “I-I mean,  _ look at it!” _

Though he didn’t particularly want to, Sans did. Apart from the cyan nimbus that had to have been there for the past few weeks (or had it been months..?), everything looked the same to him.

“Oh… oh boy! Sans, you lucky guy!”

The cyan flush pulsed brighter as realisation dawned on him and Sans faltered, covering his soul and pressing it back behind his ribs. He grew embarrassed at the attention and was at a complete loss for words when Alphys slapped both of his shoulders excitedly, unable to hide her obvious glee. Ecstatic, she hopped off from her chair and danced around him.

“You HAVE to tell me, Sans! How long has it..? Oh gosh… This is… this is so exciting. I’m so happy for you!!”

He attempted to dodge anything remotely particular, but he found that since Old Gerson’s memory on skeletons had dark pockets, he had no choice but to relent. Alphys was the brains behind monster physicality, biology and the soul, after all.

He didn’t name Grillby, but every time he said ‘someone’, Sans felt himself flush considerably. Alphys’ reactions to his observations about his body made him feel extremely anxious, but she reassured him that it was from a purely friendly biological standpoint. She was a little jittery when she patiently explained different things to him, considering it was all pretty mundane.

“This… this is great news, I… I didn’t think that, I mean-” She couldn’t resist a series of happy claps when Sans relented and gave her an encouraging grin. He was well past embarrassment at this point, and seeing the lizard lady so excited for things other than anime was a pleasant change.

That’s when Sans decided to bring up something else entirely; “so, i guess i’ve developed a sense for taste with this whole-” He stopped, gesturing to his mouth with an almost florid motion. “-i mean, i’m not used to the whole chewing thing, either.”

“That’s incredibly interesting!” Alphys agreed, her eyes piercing as she studied his face. “U-usually monsters don’t bother with that, since we just turn what we eat into, um, energy. Wait… one, one second! I’ll try to find something-”

Sans was left alone with the mess of reports while she hobbled away to her fridge, pulling select items from it in a hurry, then she rushed back. There were a few things he recognised: premade instant noodles in a styrofoam cup, sliced vegetables, some individually wrapped candies and something squishy-looking wrapped in plastic.

Curious, the skeleton watched as she prepared the items over the reports, not caring that crumbs scattered everywhere. They’d read over the majority of them, and the papers would be stored later and never looked at again until people started to eat garbage. The two were in their element, after all.

“Try this,” Alphys unwrapped one of the treats and offered it to her guest with a giddy grin. “That is, tastes are different. Chewing might be a reflex of some sort, since it’s so… so late? But if you’re only just starting, then… then maybe you’re still? Learning? Maybe? It should probably stop once you get used to things.”

“‘maybe’ is definitely the most scientific word you could’ve used there, alph.” Grimacing, Sans tested the hard candy between his teeth with an audible grunt, then he pulled it away. He didn’t like the hard things, he realised, but he couldn’t taste anything from it.

“Oh, hush,” she replied, sounding almost  _ confident _ as she waved at him to stop. Then, Alphys continued; “How… how about this, then?” She stuck out her tongue, the appendage thin and long and pink with a fork at the end. Sans stared at her, perplexed at the display. “Try it!”

“don’t got one.”

Alphys rolled her eyes and sucked her tongue back into her mouth.  _ “Make _ one, then, mister ‘anything is possible’ physics guy!”

Sans hunched into his hood with a sigh, not really knowing where to start. He supposed it was kind of like his bone attacks, in theory. Summoning one, he watched the progression of magic build up and coil into small particles of matter, calcium and structure. Alphys remained quiet, but kept a watchful eye as he experimented with his magic, only to dispel the bone again with the flick of his wrist.

Then Sans focused again, unsure, his expression fixed on the floor between them as the wellspring of magic flooded into the empty space of his mouth. It felt peculiar; a soft, thicker substance than what his body was made of. It swirled aimlessly behind his teeth as he didn’t really know how to handle it -- nor where to place it so that it lay comfortably in his mouth. With Alphys’ expectant look, he yielded the tongue forward; the same cyan of his magic, warm, and a little wet.

It was definitely a new sensation, he noted. As the royal scientist gave him an anxious thumbs up of approval, Sans prodded the tongue between his teeth with his fingers, like a child just discovering their hands. He then recognised the action and flushed in embarrassment, Alphys then giving in to a giggle.

“this is weird.”

“You.. you’ve never even tried before??” Alphys was aghast.

Sans pulled his tongue back into his mouth, his fingertips catching the tip with a tug and he hummed slightly in concentration. “nah. when you said my health would be affected due to the, uh… treatment.” He spat it out, hating to say the word, but it was easier than saying ‘DETERMINATION’, like it was a boil ready to burst. “i kinda put it aside and focused on other things, y’know? so what if i wouldn’t be able to breed later. always seemed like too much work, and i’m no good with kids. besides, i had other projects to keep busy with.”

He saw the register of guilt on Alphys’ face as the magnitude settled over them. It remained unspoken between them but he knew she felt like a lot of things went wrong back then. When it was speculated that his soul was too unstable to mate, Sans at the time had merely shrugged.

With a soft sigh, Sans reached over to pat her scaly hands, which she’d started to wring in front of her. He knew she hid a lot of the grief of the whole mess that started after the initial injection took place, which was why he imagined it was why she holed herself up in Hotland ever since. The girl really needed a confidence boost, or at the very least some comfort.

“hey. i mean it. if not for you, i wouldn’t even be alive right now.” Sans gave her an assuring grin with a gentle shrug, “so… whatever this is that’s happening now? just means it’s progress, and there’s still hope. i’m… just gonna need help studying up, since i skipped those courses.” His grin turned into an awkward grimace when she went to protest. “y’got something that doesn’t make me feel like i’m sporting stripes? or do i gotta run to the library on the way home and hope no one notices that i’m checkin’ out books meant for toddlers?”

She seemed to cheer up with that, at least.


	3. Chapter 3

**Summary for the Chapter:**

> After a memory resurfaces of when he worked at the CORE, Sans goes around fixing Alphys’ cameras in Waterfall and Snowdin after getting his cell phone fixed. Alphys proves to be a great confidant and he finally talks a little. On break, he goes to Grillby's and the fire monster proves to be a little more forward, much to the excitement of the other patrons. Seems like a bet was made.

**Notes for the Chapter:**

>  **content warning(s) for this chapter:** descriptions of dying, fear of medical procedures, brief panic attack, True Lab spoilers

The different ways of viewing his body made Sans less comfortable with the idea that it was changing. Alphys had explained the notions of ectobiology and how most non-fleshy monsters just conjured any necessary parts that they were missing. That, and she’d given him a few satisfactory college-level books on monster biology. Since he’d been unable to for the longest time and simply absorbed food as a means of replenishment, Sans found that food had turned into a whole new daunting experience.

He’d tried a few things since he wasn’t necessarily hungry, but Sans knew right away that he didn’t particularly like the sensation of things that crunched or tested the strength of his jaw, namely anything that was hard. As it was regarded as juvenile, he outright stopped himself from chewing, as difficult as it was to suppress the action. He seemed to enjoy sweet things and even something called a ‘chilli bun’, described as ‘spicy’. Alphys had explained the terms to him in relation to his reactions on the different tastes, much to her excitement.

Later, Sans went down to the basement for some vending machine chips just to try ‘salty’. It was darker than he remembered, but Alphys sadly assured him that it was only the result of a CORE flare earlier that month. With a twinge, Sans realised that it was likely around the time he and Grillby passed through.

Deeper into the lab, he consoled her about her failures after the dogs made their appearance, the long drone of at least six canines echoing through the dripping mass as it eventually retreated. Even with how hesitant she was for him to go down there, Sans already knew about the experiments. Her Determination notes and her research into making an artificial soul were everywhere. Even a few things that Sans had left behind after his treatment still hung around here and there, remnants of a past he’d give anything to forget.

The place gave him an unsettling feeling, as it reminded him of his own weakness, and no doubt Alphys hers. The place hadn’t changed at all since the visit after his accident; he could even pick out the equipment used and the bed he’d rested in during the lizard’s frantic search to stop his health from rolling down. It was an uncomfortable assessment, confronting his past.

“i kinda need a minute, alph,” Sans revealed after wandering further into the lab with Alphys on his heels. He’d grown more sombre than before, every footfall kicking up grit and grime.

“I… I understand. If anyone else visits… don’t be afraid of them. They… they won’t hurt you.”

“i know.”

Alphys lingered for a moment longer and watched as Sans shuffled into the cold darkness.

Sans felt smaller the further into the lab he went. He just needed a moment to think, to go over what had happened to him. It’d been so long since he had allowed himself to reach into just  _ why _ he closed himself off from people, playing the cheery jokester so people would like him well enough not to pry. It ended up making him recall some devilish moments, of people hurling callous statements at him and his brother-

His soul squeezed painfully, the memory hurting more when he opened himself up to it.

Being in the basement alone turned out to be more emotionally draining than he’d expected it to be. It wasn’t long before Sans deserted the idea of inward reflection and he started back.

That was when he saw it. A small pocket book, green in colour and worn from time’s hand. It had gathered the grit and grime of the lab’s basement and he shook it off, the cover and contents full of more cipher code. He frowned at it and flipped through a few pages before he realised it was filled with old notes, but in a hand he didn’t recognise. Did Alphys avoid coming down here so often that she wouldn’t have noticed that this was here? That couldn’t be right…

He pocketed it and went back upstairs, hunched in on himself and tense. He supposed that he’d have to figure it out later.

When he arrived sooner than she expected, Alphys gave him a worried smile and a look as though she was on the verge of posing a question. She didn’t, much to Sans’ relief. He went to his bag and pulled out his broken phone for Alphys to fix while he went over the reports himself.

“I have a… a request, since you’re here,” Alphys said after a couple hours of silence between them. Sans’ movements eventually slowed over time. He looked groggier the longer he tried to puzzle things together in his mind, and had started to fall asleep as a result. “Some of my cam.. cameras aren’t working. There are a few that I can’t easily get at to repair.”

Sans opened an eye and shifted his jaw in his hand to glance at her. He didn’t look very focused or awake.

“When I’m, um, done fixing your phone, maybe you could… do your engineering magic on them?” She sent him an anxious toothy grin. “I can’t monitor the Ruins’ doors, Snowdin, or most of Waterfall now. If a human came, they’d… they’d catch us all off guard. That surge really did a number on, um, my equipment. But I have all the coordinates.”

“sure. i can check ‘em out,” Sans replied after a stifled yawn.

“You look… tired.”

“it’s just my face, alph.”

“It’s also getting late,” she pointed out, ignoring his deflection. Her eyes dropped to the disassembled phone on the desk in front of her. “I’ll bring up a futon for you to, um, sleep on.”

“it’s ok. i can sleep here just fine.”

“At… at least a pillow then?”

Sans only hummed indifferently. Both of his eyes were closed now and his breathing had regulated. That told Alphys that he was done resisting sleep, and any noises he made from then on were mindless and not to be taken seriously.

He slept somewhat restlessly throughout the night. Not because of the amalgamates he knew were in the basement under them; the area brought to surface memories he’d long since put away. It interrupted his sleep like a drop of water echoing in a large empty room, the creep of memory seeping into his subconscious via dream-lengths.

Carried, Sans’ body jostled against a stronger, taller person. He was sapped of strength and clutched so tightly against their torso that he felt as though his ribs would snap under the pressure.

A high pitched whine echoed throughout his bones and in his head, and the majority of his right arm felt as though the magic inside was dead and gone. With the creep of memory, Sans felt a sting when he distantly recalled that it had made contact with the magic-matrix of the CORE.

> **[ * .9/758 HP ]**

It felt like he was sinking.

_ Hold on, brother! _

Sans heard Papyrus’ desperate voice somewhere above his head, lingering between the edge of consciousness and crackling magical interference.

_ We’re almost there! Just stay awake, Sans, you can do it. You’re doing great- _

> **[ * .8/576 HP ]**

He’d been folding in and out of awareness after having been pulled onto the scaffolding by his fellow coworkers. He barely recalled the hasty phone call made on his behalf to his brother in New Home. He didn’t remember what had struck him with the notion to lean forward and attempt to retrieve what had fallen.

All he knew was the emotion of panic, of impenetrable loss and fright as he lurched forward into the glowing mass below.

He’d reached out his arm and into the volatile energy to attempt to bring something back.

> **[ * .7/439 HP ]**

(It  _ must’ve _ been important…)

Something in him fuzzed over again like static, muffling Papyrus’ shuddering, panicked breaths and the haze of Hotland’s climate around them. He could still feel it, but it was fleeting and corroded. All Sans could really focus on was whenever his brother jostled him as his heavy footsteps kicked up the red dirt behind him.

> **[ * .6/369 HP ]**

(…important enough for him to care about losing it, whatever it was.)

He came back to consciousness after a brief lull. He was someplace definitely drier than before. The arm which had its magic stripped away by the CORE was as heavy as stone, and every part of him felt loose as though the energy keeping him together had started to crumble apart. His breaths came in soft jerking gasps as he heard Papyrus snivel over him.

He’d always been a bit of a crybaby growing up. Sans only wished that he had the strength enough to push words past his teeth instead of each laboured breath that threatened to consume his life. He just felt so heavy and knew that whatever it was, got him good. And he couldn’t even tell his brother that he loved him and that he should stay strong for him, one last time.

> **[ * .5/242 HP ]**

(He wondered why he couldn’t remember what fell…)

He felt Papyrus tremble, bones clattering through Sans’ lab coat as he tipped his skull against his own. The sounds he was making broke Sans’ heart. He wanted to tell him to be strong, that… Papyrus would be ok without him. He would learn to. He had to.

Sans didn’t want to think these things, but he knew that he was Falling Down. Dying. It was a far more laborious process than what he could’ve ever imagined. It took all his effort to remain conscious and to focus on his brother’s orange magic that flooded into him. He was starting to lose his grip on the words that pleaded with him to stay with them.

> **[ * .4/199 HP ]**

(It… had to be something that he cared about… right?)

Them? Who was ‘them’? Where had Papyrus taken him? It took everything in him to summon sight, knowing the fading flicker in his eye sockets would only hurt his brother further. The room around them was brightly lit in a cool light, blurred with his failing magic.

> **[ * .3/148 HP ]**

(Something had grabbed him… maybe. Something so hungry that it burned through his magic and still consumed him, even now.)

The colours were familiar: teal on cream. Perhaps he’d been brought to Alphys. He could hear Papyrus’ teeth chatter and his entire frame shake with sobs and pleas for Sans not to give up, for a ‘doctor’ to save his brother. To save him.

_ papyrus. _

The whisper left him, its sound hollow and more distant than how he had meant it to come out. But he tried to draw strength from the way his brother squeezed him tightly against his body, fighting back sobs.

He was a good brother. A kind brother. His best friend, through thick and thin. His… only family. 

(That didn’t seem right… wasn’t there another…?)

Something twisted painfully inside of him and Sans gasped, the action sapping him of precious reserves.

_ i’m sorry, pap… _

> **[ * .14/103 HP ]**

The sinking, heavy feeling continued.

_ You’re going to be ok! _ was his brother’s response.  _ You’re going to get through this! And we’re going to go home! Both of us, Sans… _

Sans remembered the shaky words and how they sounded so sure, like their bond could never be broken. But Papyrus also sounded scared, his words strained into a rough hiccup when someone else gave him hasty instructions in a small voice.

Papyrus’ magic had enveloped Sans’ soul as his vision swam, teetering on the brink. It was as though his brother was attempting to hold him together to prevent him from crumbling into dust. To hold him in a tight embrace full of hope and love.

> **[ * .09/39 HP]**

(Someone… fell? Was that it?)

Sans was laid down on something flat. Papyrus was still near but didn’t hold him as tight; or if he was, Sans didn’t feel it as keenly as before. He heard clicks of equipment being plugged in. Squeaky wheels on a tiled floor that made his soul clench with a trickle of unbridled fear. Monitors ran with a mechanical hum, buzzing in his marrow like a shot of adrenaline.

The magic in his eye sockets crumbled away as Sans dipped into unconsciousness for what he thought would be the last time. It’d be to the tune of beeps and circuitry laced with magic, with his brother’s despairing sobs and vehement encouragement that he could do it. That he couldn’t give up yet. He was the strongest monster Papyrus knew.

(…It  _ was _ a ‘someone’, wasn’t it..?)

He believed in him. He could do it. Sans just had to try to hold on. Even if he didn’t think he could. He heard Papyrus telling him he could do his best and he was so, so proud of him.

> **[ * .04/8 HP ]**

(Now that someone was… gone.)

His soul was pierced with something. Papyrus’ voice reeled against his blurry thoughts, rushing in to shield him from whatever was happening. Sans heard the repetitions that Papyrus believed in him.

He could do it. He was going to be fine.

He just had to  _ hold on. _

> **[ * .01/1 HP ]**

He came back to as his whole body lurched with the sensation, accompanied by the rush of Papyrus’ soothing magic around his bones. A filling spike of energy flooded him and a whip-like crack resounded through the large room.

Then everything went dark.

Sans huffed shortly as he bolted upright, his breaths coming in shallow, frantic gasps as he stared with wide eyes into the darkness. It took several minutes until he calmed down enough to realise that he was still at the lab.

Of course he was. He wasn’t Falling Down; it had been a horribly vivid dream.

A dream that regrettably,  _ had _ happened.

He cupped his hands over his eyes and lay down on his back. Apparently during some time that night while he was asleep, Alphys had draped a fluffy yellow blanket over him and gave him a pillow.

His gaze dropped to it, then he flung off the covers. After such a gruesome reminder of his accident, it’d been a nice gesture. Though it was a strange one, considering he normally didn’t feel chilly. But Alphys was a lizard monster, and he knew that regulating body heat was important for her kind, so he didn’t belabour it too much.

Sans looked inward.

> **[ * 5 HP ]**

Thoughtfully, Sans sighed softly and gave in to a bitter laugh as he rubbed at his breastbone. It’d been awhile since he allowed himself to remember any of that. The accident, coupled with the state he was in when he returned, and the fact that he had to come to terms with new limitations…

His entire body had been a mess the months following his near-miss with death. It took Sans even longer to feel comfortable in his own body again. No one at the CORE site remembered if anyone had fallen into the magic-matrix, apart from himself.

As a result, people started to treat him differently. Papyrus became protective of him and Sans secluded himself from others to avoid the pain of pity. It was part of the reason he didn’t want to live in New Home anymore, where everyone knew it’d take only one hit and he’d be dust. So after a few decades of rehabilitation and working with the teams to tie up a few projects, Papyrus and Sans left New Home for a quieter life.

He groaned to himself, the itch just behind his ribs worrying enough for Sans to pull his soul out of hiding. Nothing had changed between then and the previous night save for a small HP buffer.

Determination was complicated in that it didn’t leave any visible traits on the soul; otherwise it’d have a golden hue instead of its usual cyan-white. It simply anchored Sans to the world at the point when it was injected into him, and since his physicality was comprised in the fibres of his bones, and bones was all he was really made of, Sans would be the only success amongst Alphys’ experiments.

Everyone else that followed… was a different story.

The clock showed that it was still incredibly early, but he could hear faint rustlings upstairs. Deciding that it was probably best for him not to fall asleep again, Sans pushed himself up and headed to the kitchenette for coffee.

The assessment: sour and bitter. Alphys gave him sugar for ‘sweet’. Much better. It was quickly becoming one of his favourites.

He didn’t mention his dream to Alphys; instead, he ignored it and slung the pack of tools required for repairs over his shoulder. Then he was supplied with the first coordinates for the camera that had glitched out in Waterfall. Alphys had returned his phone with some minor upgrades, which included the ability to capture video and sported improved waterproofing, since he lived in a snowy climate.

Alphys was used to his shortcuts, but she would marvel at it every time. The two kept tabs while on the phone and Sans reappeared in Waterfall.

He exhaled a sigh of relief when he didn’t arrive in  _ that _ corridor again. Instead, his slippers hit the familiar wet surface of the docks beneath the first waterfall, where he had first revealed to Grillby the nature of his shortcuts.

Sans couldn’t help but smile and flush at the reminder of Grillby’s amazement. He realised that it had been one of the few times that he’d allowed himself to feel a little proud of himself, rather than ashamed.

He continued on and peered behind the rushing water until he found a camera just out of view. Cautiously, Sans took off his hoodie and dropped it onto the bridge before he attempted to cross the narrow gap. He sputtered briefly and ducked away from the fall of water, entirely inched between the space beside the fried camera with his toolbag.

It didn’t take long for Alphys to call him; it had been their plan. She would give instructions on where to go and help him troubleshoot, then give the ok when she had the video feed back on her end. When his phone rang, Sans opened his mouth, relieved that he could now do so and he let the marsh water out of his skull. That was a plus, at least.

“yo,” Sans answered, suspending the phone midair with his magic as he worked.

“I just… wanted to say, how very thankful I am that you’re helping me! And also, I have another negative report from yesterday, i-if you’ll allow me to, um-”

Sans grabbed a screwdriver out of the bag and shimmied his body to the side, the narrow ledge not quite wide enough for him to turn comfortably despite his small size. He could only imagine how difficult it would’ve been for Alphys to get here, let alone do repairs.

“really. where abouts?”

“From, actually, uh, just inside Snowdin? Looks like it’s pretty close to one of your boxes.”

“oh,” Sans murmured, using his teeth to hold a small pair of pliers. He felt himself flush at the memory of Grillby’s tease and how close he’d gotten. That, and also how desperately nervous he became over the prospect of asking him out. That was an embarrassing scenario, he recalled. “yeah, uh… that was me.”

“The thing is? Where did you go? I… I mean, usually there isn’t much time in between jumps? But… the corresponding end-gap by the ferry stop didn’t appear until… almost three hours later?”

Sans paused when he recognised the worried tone in her voice. Her sentences always aborted prematurely or restarted as though her thoughts tumbled in her mind faster than she could process.

“uh.” It was Sans’ turn to struggle but he found it easier knowing that she couldn’t see him hesitate. “i might’ve gotten stuck.”

“Stuck!? Oh… oh my god???”

“alph. hey, i’m ok. i got unstuck.” Pressing his teeth together, Sans realised that he’d spoken without thinking it through. He hesitated and while he could hear Alphys’ breathing, he felt like he shouldn’t take too long. “ok. lemme explain.” More hesitation. Frustrated, Sans rubbed at his neck in thought. “well… starting out, i had a buffer. nine points, maybe. don’t remember. anyway, i found a door.”

“I… I, I don’t, uh, have coordinates for-”

“it’s cool, alph, i don’t ever wanna go back there,” Sans replied dryly, the revulsion of the place echoing in his memory.

“Why? Wh-why didn’t you tell me when you got here!! I… I asked, and… when I checked, you… you didn’t  _ have  _ nine points, Sans!”

“i know,” Sans repeated, beginning to sound a little testy. He adjusted himself and sighed, flipping the side panel of the camera open to inspect it. “whatever it was, i couldn’t  _ not  _ open that door. like it was some kinda weird compulsion that i couldn’t shake. have you ever heard anything like that?”

“No… no, I don’t think so…”

“then,” Sans hesitated, thinking quickly, “what about monsters that feed off of magic?” He paused, then added with a grimace, “other monsters’ magic.”

There was a long silence that accompanied Alphys’ stuttered breathing. Sans allowed her to mull it over while he worked, prying wires free and lighting the area with his magic to see better.

“I… don’t think I’ve ever, ever heard of that?”

Sans hummed thoughtfully, flicking a digit against the panel inside the camera irritably. It sparked in protest until it produced a quiet  _ blip. _

“ok, well. how about this: do any monsters you know feed on light?”

“On… on  _ light?” _

“yeah, like… when i opened the door, i thought i saw someone. not like any monster i’ve ever seen, not out where i live now nor at the capital.” Sans shrugged, as though the action emphasised his internal discomfort. “and… i guess i could feel it. like, they were trapped, and whatever magic i could muster, just kinda…” Fizzed out? Dropped?

_ Consumed. _

Sans stopped with the invasive thought. He recalled the disquieting mantra that had repeated in his head in the room beyond the door. Thinking about it made a finger of pain trace the inside of his skull like a papercut. It was better not to bring it up, then.

“That… that sounds worrying. I’ll… have to run some scans. But… why talk about it now? Why not when I asked? Or? May.. maybe, I-”

“eh, alphys. it’s not you, i just… can’t really talk to people face to face with this kinda stuff, ok?” Sans’ voice softened. His mind started to whirl into two different directions: one of his scare in the place that looked like Waterfall, and the other of the connection he was drawing from his accident. “and, y’know, i kinda needed to think it over. it doesn’t make a lotta sense, now that i’m talking it out.”

“I… I understand. I’m sorry.”

“it’s ok. you don’t gotta be.” He decided to come clean. “the truth is, uh… i had a dream last night.”

“Oh..?”

“got me thinking that it felt really familiar, being behind that door with some unknown monster absorbing my magic like it’s friday night wings,” he groused. It was a feeble attempt to make light of the feeling, when it really felt dark, cold, and foreboding.

She ignored the joke. “Fam.. iliar? How?”

Sans stopped adjusting the camera and took a hasty glance at the hovering cellphone by the cave wall. “uh… when papyrus brought me by.” Silence from the other end. He took a calming breath, trying to sound as though it didn’t bother him at all. “when i was falling down.”

“Sans…”

“i know i’ve never talked about it. i’m kinda garbage that way. it’s just easier  _ this _ way. when i got eyes on me, i freeze up, right? you know me. i’d rather hide and joke until shit like this blows over, but, turns out that i, uh…” He paused and shrank back against the rock face, then tipped his head up and watched the water rush down from overhead. “i… i can’t talk to pap about this kinda stuff. i’ve tried. he assures me i’m ok and everything is the same as it was before, but i know he worries. so i end up not talking, and i really hate lumping this crap on you-”

“Y-you can always talk to me, Sans! Even… even if you just need to sort out your thoughts, or get something off your chest, or vent… a-anything!”

Feeling a twinge of remorse, Sans muted a sigh. “do you have the feed?”

“Huh?” There was a pause, then a shuffle from Alphys’ end of the line. “Oh yeah, yes we do! Thank you so, so much!”

Sans stayed quiet as he manoeuvred over the gap with his bag of tools, then picked up his hoodie. Even though the crossing had been brief, he was soaked to the bone.

“ok, next coordinates.”

“We… we can still talk? That is? If you need to. There isn’t any rush, Sans.”

“one sec, alph.”

Sans shouldered his bag as he looked around, relieved that there wasn’t anyone nearby to eavesdrop. In fact, he hadn’t considered the echo flower that grew at the opposite side of the bridge and whether or not his voice could’ve been picked up by it. So as carefully as he could without making a sound, Sans walked over to listen.

_ ‘I swore I saw something… Behind that rushing water…’ _

He was safe. After all, he didn’t need a repeat of the morose realisation monsters had at New Home when he came back from Falling Down. Quickly, he walked up the bridge to the side of the eddying pool and took the phone in hand, preparing for another warp when he saw that no one else was nearby.

“coords, alph?”

“Wha--oh. Right.”

Tactfully, Sans glossed over the reason why he shouldn’t go to the Snowdin sentry station right away, where another camera was broken. He didn’t need a run-in with his brother right then. Instead, he was given the coordinates for the one by the Ruins’ door, hidden out of sight in a withered and snow-covered shrub. It would certainly be easier than the waterfall-hidden device.

“Did… did you still want to talk?” Through the speaker, Alphys’ voice was inquiring and quiet as he got to work. Nonchalantly, he dumped the toolbag onto a snow pile at his feet and inspected the camera through the brambles.

“kinda chilly,” he remarked, voice muffled by the end of a screwdriver. Oddly enough, his teeth spasmed tighter around the handle, trying to bite by themselves. To chatter and shake with the cold. Weird.

“I guess this whole…” Alphys faltered for the word before settling on,  _ “…puberty _ thing must be throwing you for a… for a loop, huh!”

“was really hoping you wouldn’t say that word.”

“Ok! Well? Maturation? Genesis?  _ Sexual awakening?” _

Sans sputtered, dropping the screwdriver and pliers into the snow.  _ “alphys!” _

Sans heard her incessant giggles through the crackling phone line, long enough for his thoughts to wander to warmer things. ‘Warmer things’ being a certain fire monster and the heat he brought. Sans’ mind then went to the memory of him at his station, feeling cold under snow before Grillby filled his body with fire. It moved on to the kiss, of the fire monster’s hand against the bones at his chest as he touched him in kind. He felt flush, then he made a coughing sound to indicate his discomfort at Alphys’ laughter.

“Eh, I’m… I’m sorry, Sans. I know I shouldn’t be laughing…”

“y’know, after paps finished puberty, i thought we weren’t gonna have to deal with this again.” Sans rubbed idly at the side of his skull, his thoughts still wandering off the project at hand. “i, uh, might… take a break after this one. i’m kinda soaked, and i’m freezin’ up here.”

“Of course! Managing your temperature is extremely important!”

He stooped over to retrieve the fallen tools, feeling his wet clothes start to harden and the water in his joints start to ache as it froze. Carefully, he bent his knees to keep them from locking up with ice. It seemed colder than usual today.

“Hey… wait? Skeletons don’t have skin!”

“nope.”

“Then..?”

“got waterlogged. and it’s cold.”

“How can you, um, even tell?”

“my joints hurt when water freezes in ‘em.”

Sans shrugged to himself as he pulled the wires from the camera. Then he thought better of it and tugged the whole mechanical housing right out of the bushes. Unfortunately, it got snagged and Sans had to give it a hefty tug with a bit more force, which sent him onto his back in a heap of snow with a surprised grunt.

The heavy camera landed square on his rib cage and he hissed softly, pulling it away from him and rubbing the spot of pain through his hoodie.

“Sans!? Are you, are you ok??”

“not gonna lie this time, but i think i lost a point and my carpals and tarsals are freezing up.”

Shuddering, Sans brushed the snow off the device and gathered his tools. It took him awhile to find the screwdriver, the cold settling into his joints and making him still. He rattled to shake out the ice that had formed.

“m’gonna head off to get dried out.”

“Out?”

_ “off. _ i meant  _ off,” _ he chattered, embarrassed over the blunder. “i’m goin’ to grillby’s and taking the cam, so i’ll text you when i’m done.”

That done, Sans hung up without further explanation and stuffed the phone into his pocket. Then he trudged a few agonising steps towards the nearest rift before reappearing around the corner from the bar in Snowdin. He continued to shiver as he climbed onto the stoop, his soul thundering when he pushed the door open.

Sans knew he had told Grillby that he’d be gone for a few days and it had only been one. It was nearly lunch time so the bar wasn’t filled to capacity, but a few regulars were there. Red Bird, Ugly Fish, Doggo, the two crooning dog sentries, and the tipsy bunny. Sans waved with a crooked grin as a couple greeted him, but he stayed near the door when his gaze found the owner behind the bar.

It took him a few moments before his feet were sure enough to walk to the counter without Sans feeling like a fool. He attempted to keep the rattling to a minimum, but he couldn’t help the way his hands shook as he climbed onto his usual seat, though the stool had been replaced. He swung his bag and the camera onto the bar top out of the way, then Sans leaned over the counter, his bones tingling as heat gradually sunk into them.

Grillby put a towel to the side before leaning over the bar himself, the curl of his mouth forming a pleased smile.  _ “Didn’t scare you away?” _ His tone was softer with an audience around them.

Sans hummed quietly, tilting his stool forward to get closer. One would think he would’ve learned after his previous tumble, but old habits die hard.

“couldn’t keep away.” His reply was a murmur as he folded his arms over the counter, but he remained upright. Sans’ gaze lingered on the fire monster’s face and he grinned. Then something caught his attention behind Grillby, at the row of glasses and under all the bottles of liquor. Anxiously, his soul began to thrum behind his ribs when he caught the familiar sight of Waterfall blue.

His gaze then darted back when Grillby’s hands inched towards his own, the moment spent at his sentry station replaying in his head. Sans felt himself flush at the reminder and a shiver passed through him. As one of Grillby’s hands brushed against the side of his face and traced a warm line down his jawline, Sans inhaled a little sharply, bowing his head.

_ “You look absolutely… chilled?” _ Grillby sounded amused as Sans leaned against his warm gloved hand, delighted with the skeleton’s reaction. He was vaguely aware of a few other patrons watching and Grillby smirked to himself, his other hand against Sans’ fingers itching to encircle them.

The skeleton hummed softly as the heat flooded into his skull, enraptured by the affectionate gesture. In turn, his own fingers automatically clasped Grillby’s, the sensation of holding hands oddly titillating. Sans realised that beyond the confession, he didn’t really know how to progress into the next stage of their relationship, whatever that meant.

Something under the rows upon rows of alcohol drew Sans’ gaze again. Behind the bar he found a small blue vase, filled to the rim with glowing water. Something inside of him sighed when he recognised the small, beaten up little echo blossom suspended within it.

Sans had forgotten about it, left behind and out of sight. It looked as though the fire monster had taken it upon himself to preserve it. Sans would’ve imagined how the fire monster looked; careful not to burn it, cautiously funnelling water into the jar, perhaps focused intently to keep his temperature down so its contents wouldn’t boil.

Grillby took notice of Sans’ stunned silence and looked over his shoulder to where he was staring, his warm hands withdrawing as he turned.

“you kept it.”

_ “Naturally. It’s one of the most beautiful things I’ve ever received,” _ the bartender replied, his expression beaming when he turned back. Every word was accentuated calmly and every hidden detail crisp as he leaned forward to close the distance between them.

When Grillby drew nearer, Sans felt his warm breath against the side of his face, words lowering in register so only  _ he _ could hear.

_ “To serve as a reminder for… when I get to hear it directly from you.” _

The smooth tone and just the right amount of tease had Sans disarmed and leaning forward, silently yearning for more. His mind was focused solely on the bartender so much that it barely registered that the stool was at jeopardy of swivelling out from under him again.

Grillby laughed softly in his throat as he mercifully caught him. Each hand grasped Sans’ upper arms and Grillby allowed him to settle once the stool stopped its skidding against the floor.

_ “Why don’t you take a booth, Sans.” _

Suddenly, the sounds of the restaurant came flooding back to Sans, reminding him that they were very much  _ not alone. _ He felt a peculiar kind of apprehension then when he heard the soft gasps and croons from the dog couple with their little display, enough to make him turn his head.

“I’ll have what  _ he’s _ havin’, Grills,” the red bird drawled as he spread his wings over the bar top and gestured plainly to the skeleton.

With an insurmountable ebb of mortification, Sans shrunk down away from Grillby’s touch, his eyes resolutely fixed on the marble bar top.

_ “……Sloppy Joe,” _ the fire monster replied after a beat of hesitation, like he had forgotten where he was too. He threw the bird a knowing glance, a subtle flutter of warmth coming off from him with a wink as he moved away from behind the bar.

Bravely, Sans looked around them and bore witness to the doting and encouraging way Dogamy and Dogaressa applauded them, even as Doggo bumped elbows with Red. The buff canine puffed a long breath from the lit treat before giving the bird a smug grin, elbowing again. Then again, insistently. Red didn’t look too upset at the implication, but it left Sans feeling a little uneasy.

That is, until Grillby rounded the bar and gestured towards the closest empty booth. Sans couldn’t help but awkwardly grin, still feeling bashful at the fire monster’s rather public display of affection.

“is it, uh… ok if i tinker here a bit?”

Grillby rolled his shoulder as he took his place beside the booth once Sans had sat down and slid his bag and the broken camera across the tabletop.

_ “Would not bother me in the slightest.” _ He tilted his head then as Sans reached for the menu. With how often the skeleton came for meals and drinks, he found it peculiar how Sans went for a menu  _ now  _ of all times.

“thanks, g. funny how, uh…” Sans faltered, not really knowing what to say nor where that sentence was leading to. He used the tall menu to cover his face and hide from Grillby’s perplexed look, making a show of perusing the drink section. His face was burning. “what, uh. what drinks do you recommend to a guy who’s… taken a liking to sweet things?”

The fire monster didn’t reply, but when Sans finally had the courage to look up at him, Grillby was smiling pleasantly. Sans couldn’t help but return it, his own grin feeling out of practise and off-kilter. After a moment, Sans felt as though Grillby’s smile intensified, then the bartender left him be.

Sans watched as Grillby retreated, lowering the menu so his eyes could follow him back to the bar. As Grillby passed the two suspicious monsters, Sans could’ve sworn he heard the subtle rasp of coins sliding across the marble counter top. Doggo’s grin became smugger as he tossed and caught the moving gold mid air, much to the bird’s apparent chagrin.

**Notes for the Chapter:**

> Because of the nature of the writing and Alphys' assessment, I gotta come clean and say that YES Sans is an adult in this fic. I hope that came across because I got a message on tumblr that it seems… skeevy. Papyrus definitely passed puberty, Sans didn't, due to his accident & recovery process and other factors. Because of limited info on skeletons in the Underground, the whole thing is a mess, hence Sans' confusion. Sans is 120y and Papyrus is 112y, monster age approximate to mid 30s/late 20s.


	4. Chapter 4

**Summary for the Chapter:**

> A skeleton walks into a bar. While it appears that he is different, he is not. A certain fire monster can't help but interrupt while Sans attempts to tinker.
> 
> Grillby POV. Teasing & flirts. ♥

True to his request, Sans started his work at Grillby’s. The fire monster had brought him something called ‘crackle soda’ and waited on him to try it. Sans did, holding the drink in his mouth while it fizzed; then his magic absorbed it.

 _“How do you find it?”_ the fire monster inquired, having watched with curiosity. He had gathered rather quickly that there was something about Sans that had changed, and not necessarily for the worse, either. The part in his teeth was new. It took every ounce of his self-control not to outright drop what he was holding in shock when he noticed it upon Sans’ arrival.

“sweet,” Sans reported, then he attempted another sip from the straw. Curiously, his brow scrunched in thought as he felt the fizz of bubbles against his tongue. When it absorbed into his body, he added, “i like sweet.”

As he continued to watch, Grillby thought that it was a particular assessment to observe. It was interesting to view Sans in such a light. There were subtleties that by all means should’ve been _normal,_ yet it had been so long without them that it simply didn’t seem out of the ordinary, until now. Sans remarked on tastes with an almost childlike wonder and even asked for recommendations as though every meal he’d ever consumed had been forgotten. Grillby was hesitant at first, but became encouraging when he sensed Sans’ unease and self-consciousness.

 _“Perhaps try an old favourite?”_ he offered, leaning against the side of the booth to reach over the skeleton’s shoulder. He then turned a page of the menu and pointed down the row of selections. What could only be described as a nervous chuckle escaped his friend, caught at the end. Sans shifted on the cushioned bench and Grillby caught the fleeting glance up at him before Sans’ gaze shot right back down again.

“maybe… pick something you think i’d like,” the skeleton replied hesitantly, his tone quiet.

Grillby’s mouth curled into a soft smile as he leaned down. _“Indecisive,”_ he whispered beside Sans’ skull, a hint of amusement to his voice hanging between them. _“That’s not like you.”_

He watched as a subtle shudder passed through Sans’ shoulders and Grillby could feel his temperature rise at the reaction. His smile broadened slightly, but he remained courteous and awaited Sans’ response.

“still kinda new to all… this,” Sans finally murmured. His bony digits snuck up to tug at one side of his hood as if to hide. Grillby caught the way his glance darted up to him again and he gave Sans a gentle smile of reassurance. “…maybe i’ll stick with the sloppy joe.”

 _“Honestly…”_ the fire monster breathed as he leaned up and away from Sans. It was as though Sans went out of his way to be noncommittal and hesitant about every choice that he encountered. _“You speak as though you’ve never eaten here before.”_

A creep of cyan flush settled into the skeleton’s face with that, and although he liked the reaction, Grillby couldn’t help but feel a twinge of regret for making him uncomfortable.

“i, uh,” Sans mumbled, then his voice dipped in register as the words tumbled out inaudibly. Grillby blinked and leaned down again, his face closer to the skeleton’s head so he could better hear him. “your food’s always been great, grillbz, just… i’ve just come about actually, y’know… _tasting stuff_ lately.”

The bartender tilted his head; he hadn’t expected for Sans to be so forthright with the information, but it certainly explained a lot.

_“In general, or..?”_

“yeah. better late than never, eh?”

 _“You have… never tasted before,”_ Grillby repeated quietly. Though his tone was mildly amused, he couldn’t help but feel pity for Sans. He knew how old Sans was and all, so it surprised him to know that for all this time, Sans was missing out on such a thing. Something that other monsters took for granted, at that. _“However did you reach the conclusion that my food is good then?”_

He watched as Sans shifted on the bench again; this time not looking up at him but towards the long-broken jukebox at the other end of the room.

“i guess… absorbing it always went down easy, so in some way i always knew. and everything smells great, i never really questioned it. just figured it had to match. you put so much effort into how stuff looks on a plate, how everything is arranged perfectly. i can honestly tell you love doin’ what you do. and everyone looks so happy eating it.” Sans gave a slight shrug at the revelation, then slowly turned his skull to look up at him. “i guess i’m just… kinda intimidated now. heh.”

Grillby couldn’t help but chuckle at that and even moved to pull his hand over the flames atop his head. It was a fluid motion, hand settling at the base of his neck. It was encouraging and flattering hearing Sans praise him right to his face.

 _“Surprised you hadn’t considered ketchup, to be honest,”_ Grillby teased through a soft laugh. He met Sans’ gaze, whose eyes had widened slightly as though, no, he _hadn’t_ considered it.

“i’ve been drinking it this whole time ‘cause people’s reactions are hilarious,” Sans replied candidly, though he shrugged off his slight shock. “what if it’s… not actually that great?”

 _“Would not be missing out on much, my friend,”_ the bartender responded through another ethereal chuckle. Without missing a beat, he leaned over the skeleton again to fold up the menu and return it to the side of the booth since it was no longer needed. The perfect surprise had just come to mind.

At Sans’ questioning glance, Grillby gave him a wink. _“At any rate, forget about what’s arguably my least popular menu item. Will create something more palatable… just for you.”_

Before Sans could object, the fire monster turned and left, his heels clacking on the hardwood floors. Grillby couldn’t help but notice how his patrons had fallen silent throughout their exchange. There were one or two more pairs of eyes that followed him, and there were new customers waiting to flag him down.

Quickly, he took their orders and sent a quick glance to the skeleton off in the corner of the bar. He caught the look he was given in return and smirked to himself when Sans turned his head, more of that delightful cyan flushing his friend’s face until he was out of view.

Grillby couldn’t help but dare to think that Sans was rather charming just then.

“(He’s obviously sweet on you, Grillby-darling,)” Dogaressa said as he passed, causing him to stop at the couple’s table.

The attention brought his temperature up a couple degrees with the startling realisation that _all_ his patrons likely knew by now of his and Sans’ tender little moment. After all, the Dogi had walked in on them that evening and Snowdin was a small community with little else to talk about. They had probably mentioned something. At the same time, Grillby was nothing if not _forward_ with his affections when Sans had arrived earlier on.

He didn’t give a response to such an observation; like many of his exchanges with his patrons, they tended to be one-sided. There just didn’t seem like any addition he could muster for their consideration. Instead, Grillby beamed brightly at them both before taking Dogamy’s order, then retreated to the back kitchen to put his culinary arts to the test.

With so many orders on the go, Grillby rushed to get the other patron’s food out first. He wanted to savour Sans’ reaction once more, this time to a hearty bowl of cinnamon-spiced squash soup. He recalled that Sans liked sweets, and while it wasn’t necessarily his own favourite, he wanted Sans’ first experience to be special.

Grillby put extra care into it, the bouillon lightly caramelised with his fire magic and he seasoned it just right. As he added a sprig of clove and rosemary to garnish the soup and a milk bun with melted butter to the tray, he scrutinized over every last detail until he was sure it was perfect.

Admittedly, he was concerned about what Sans’ reaction would be. He said all of his food was _good,_ and yet Grillby felt the need to make a great first impression now more than ever. It was as though the King himself was coming to visit, but somehow, this seemed like a greater deal to him.

He loved him, after all. If his affections were enough to make Sans tremble and shy away, perhaps this would ease his worries? Grillby knew that fire monsters were widely regarded as bold, so he secretly hoped not to scare Sans off again.

There was a lull in customers by the time he exited the kitchen with his dish; Grillby almost breathed a sigh of relief. He could feel every eye on him as he calmly walked from behind the bar with the tray of food and towards Sans’ booth.

The skeleton had absorbed himself in his work, occupied with a disassembled device that once looked like it had been a camera. Sans’ brow scrunched up in concentration, a small screwdriver held between his teeth as he attempted to fiddle with the innards behind a panel. Then Grillby saw a spark and a muffled swear escaped Sans, bony digits flicking as though to shake away the pain of a shock.

The bartender lingered a small distance away to watch, as it didn’t appear that Sans had noticed him. That was a feat, considering Grillby was a natural light source. He merely stood by, gradually inching forward step by quiet step until he lingered next to Sans, following his precise movements with burning curiosity.

It was the first time that he ever really saw Sans concentrated, hard at work. While Grillby knew that he was a sentry in Snowdin and areas nearby, Sans had alluded to his past work at the CORE with infuriating vagueness. An engineer of sorts, Grillby recalled. It was just so perfectly endearing to see the skeleton wrapped up in his own little world. Occasionally, Sans would be pulled from that world, pausing only once or twice to check his buzzing cell phone.

Then Sans looked up, having noticed him. Ah, that was short-lived. Quickly, the screwdriver was taken out of his mouth and Sans gave an excusing grin to the mess on the tabletop. He rushed to pluck away bits of wire, screws and film over to one side so that there was a place for him to eat. Grillby had a vague feeling that Sans normally just ate over his work. The action made him feel a little special.

“didn’t see you,” Sans pardoned himself a little hastily, then looked at his phone again. Distracted, he turned off the screen and shoved it into his pocket.

 _“Wasn’t sure if I should interrupt,”_ Grillby replied, setting the bowl in front of Sans along with the small plated bun. He watched as the smaller monster looked at it, unsure. Then Sans glanced up to him, as though asking permission. _“…Go on.”_

A shy but excited grin tugged at Sans’ teeth and Grillby couldn’t keep himself from returning it, even when Sans turned his attention away to the meal. Sans just stared at it, both of his hands relaxed on either side of the bowl in silent appreciation.

Carefully, Grillby sat at the opposite side of the table, his flames flickering in a peculiar way. Sans mulled something over, but he quickly recovered when he saw Grillby’s movements.

Grillby agonised internally, hiding his expression behind a veil of fire. Perhaps Sans didn’t like what he saw? It wasn’t his _usual_ method of cooking, after all.

_“Sans?”_

Sans couldn’t help a snicker, then he let out a full out laugh. “i’ve been _stew_ ing on it, but i can’t come up with any _soup_ reme puns,” he chortled, and Grillby exhaled hotly, visibly relaxing where he sat. He couldn’t help but chuckle.

As Sans looked rather pleased with himself, he grabbed a spoon and dug in.

It was interesting to behold; Grillby was 100-percent certain that a tongue was _definitely_ something he would’ve noticed before. Considering that it was the first time he’d seen Sans even _open_ his mouth, Grillby corrected his thoughts on that. No, he wouldn’t have noticed; it simply wasn’t logical for him to know. His flames danced around his face with the first mouthful of soup and the heat of Grillby’s core spiked when Sans quietly hummed after a moment to savour it.

Grillby waited as Sans had a bit more, almost holding his breath every time the tip of a magic, cyan-coloured tongue inched from Sans’ mouth to meet with the spoon. Grillby couldn’t help the searing heat that scalded through the flames of his face and neck at another one of Sans’ appreciative hums, pleased with his reaction.

 _“…How do you like it?”_ It took everything in him not to immediately demand an answer to calm his excited fire. Grillby gripped the tray on his lap tightly as he waited with bated breath, his soul pounding anxiously for a response.

Sans smiled after another mouthful with an amused chuckle. Once his magic had absorbed it, his smile tugged into a wider grin and his posture became more relaxed.

“it’s really good,” he admitted. “sweet… kinda spicy. feels warm, too, right here.” He patted his chest and with the audible _thump,_ the cyan flush returned.

Grillby leaned onto the table with one arm, a content smile curling at his mouth. He was glad to hear it. Intent was everything. He had put a lot of care into his cooking, as it was made especially for Sans. So if Sans could feel it in his soul, it kindled a tenderness in Grillby in response, pleased that his efforts could affect the monster he cared so much about.

A buzz from Sans’ pocket interrupted him from continuing his meal and Sans sighed softly, putting another spoonful into his mouth. He left it there as he took the cell phone from his pocket with a veiled glare, tapping out a response.

 _“Papyrus?”_ Grillby couldn’t help but quietly wonder.

Sans pulled the spoon from his teeth, absent-mindedly licking the remnants as he read the reply that came seconds later. Grillby felt another hotter flush pass through him and his eyes darted to the side as Sans set the utensil away without a second thought. Willing himself to calm down, Grillby swallowed thickly; Sans didn’t appear to notice.

“nah. alphys -- the royal scientist. i’m helping her with some repairs. she’s getting antsy. should probably call her in a bit…” Sans replied, then his gaze found Grillby and his paler flames. The bartender sensed his curiosity and shifted his gaze back, offering him a pardoning smile.

 _“Have you spoken with him, though?”_ That piqued Grillby’s curiosity now. With Sans’ inquisitive look, which then shifted to sudden realisation, the fire monster couldn’t help but laugh softly.

“uh… no,” the skeleton replied, his voice dropping in volume. “i think he kinda suspects something’s happened though.”

_“Between us?”_

Sans’ flush deepened, as though the memory had crept up on him. Grillby took a moment to reflect on it as well, curling his fingers under his flaming chin. Yellow flames started to peak along his face and he almost preened.

 _“Bashful skeleton,”_ Grillby murmured after the moment passed. He couldn’t help but delight in the way Sans shrunk down, every inch of him the perfect picture the fire monster had described. _“You really haven’t breathed a word?”_

Sans drummed his fingers on the tabletop before stopping abruptly and he looked down to his phone. Then he shrugged. “i dunno how, to be honest. he kinda helped.” Sans stopped as though to reconsider his words, then he seemed to come to a realisation. “he doesn’t know it, but he, uh… it was his idea. the, um, the flower.” His eye lights flicked over to the bar, where the echo flower was safely kept behind the counter.

 _“Matchmaker Papyrus,”_ the fire monster breathed, feeling a blossoming appreciation for the brother’s interference. _“Long is the list of titles bestowed upon him as of late.”_

Sans had to chuckle at that. “he’d strut around and gloat to know he had a hand in it,” he agreed. “i can’t let him have that satisfaction after all the badgering.”

_“Satisfaction?”_

Sans shrugged somewhat bashfully, raising his hand to scratch at his jaw. “i told you, i’m new to this. he just… convinced me i had to say it for myself. then it went from there.”

 _“Found the courage.”_ The bartender then hummed, feeling his soul fluttering with the thought. _“I’m so very glad you fell off that stool.”_

Sans held back an embarrassed laugh that ended up sounding more like a giggle. He cradled his skull in one hand, his gaze drifting to the bar again in a sidelong glance.

“me too.”

The extended lull in activity in the restaurant provided them with enough time to chat amongst themselves, mainly occupied with the idea that Papyrus would eventually find out about what had happened. Grillby came up with an idea.

 _“Could always subject him to a prank,”_ he suggested with a shrug as Sans polished off the rest of the soup and bun.

Sans sighed and leaned back against the polished wood of the booth, seemingly sated from his meal and a sleepy smile on his face. He closed his eyes and relaxed, his voice dipping in register, “a prank, huh? been a hot minute since i’ve done that.”

Grillby noted the subtle glow poking from Sans’ collar and leaned forward, examining him as he considered it. It appeared that Sans had recovered from his anxious state earlier and was much more like his usual self. The conversation was no longer quite so hesitant or quiet.

“what do you got in mind?”

Grillby thoughtfully tapped a single digit against the tabletop. _“Pretend to have lost the flower. Pretend that you’re worried who might find it. Tear up the house looking for it.”_

Sans opened an eye to regard Grillby, whom was giving him a devious smile. “that’s laying it on kinda thick.” He snickered. “you’re such a devil.”

Grillby offered a shrug, a bloom of heat rushing through his flames. _“Fire monsters are known to be hellish.”_

“and here i thought you fell from heaven,” Sans automatically drawled, tapping his fingertips against the top of the table again. Then his grin dropped briefly as another flush flooded his face, realising what he’d said.

Grillby kindled noticeably paler; had Sans really meant to say that? It was flattering and ridiculous, and… so _Sans._

 _“Well… stars produce fire, so not far from the mark, I suppose,”_ Grillby murmured through a crackle, his flames returning to their normal shades.

“i keep forgetting to freak out about that. is that a thing i can do now, or would that be weird?”

Grillby was at a loss for words, but he managed to hide it well. Instead, his eyes flitted briefly to the opposite end of the bar and he couldn’t resist a shy smile. That’s when he became quiet and contemplative. Speaking of stars in the Underground always made him feel a little uneasy, even if he hid it well. Apart from a select few, he’d kept the nature of his exact existence a secret since he moved to Snowdin.

That is, until he chose to tell Sans.

“i, uh. i didn’t mean to make you uncomfortable,” Sans murmured as he raised his hand to his skull and scratched his temple.

 _“As long as it doesn’t reach Waterfall,”_ the bartender admitted with a slow nod, though he concealed the threatening grimace. Sans must’ve recognised it, as his expression gradually softened. After a moment’s pause, Grillby added, _“People there get, ah…”_

“worshippy. i gotcha. not my first stroll through the place.” Sans gave him a knowing grin as he settled both of his elbows on the table. He pointedly ignored his phone, which buzzed intermittently throughout their conversation.

It was Grillby’s turn to lightly tap his fingers against the tabletop. He saw Sans follow his movements and Grillby found himself gesturing in a way to shrug it off.

_“Before you ask… the wish thing is a fable.”_

“i’m not really interested in that,” Sans immediately replied. Grillby couldn’t help his reaction; a startled jerk as his back straightened where he sat, openly staring across the table.

Well, that was a first. He certainly hadn’t expected that; but lately Sans had started to open up to him in new and interesting ways. Indeed, even now, the conversation was along the same vein as before. Easy words exchanged, poking fun at each other. Only now it was more fun and flirtatious, and the fleeting touches shy and unsure. Their friendship had started to become something deeper and more meaningful with every interaction.

“i’m more interested in…” Sans trailed off and paused to carefully consider his next words. _“are_ you technically a fire monster?”

Amused, Grillby gestured to his torso as though it spoke for himself, the movement lithe and smooth despite his crackling noises. It wasn’t a question he had prepared himself for, so far, and he didn’t exactly know how to respond.

“ok, fair point.”

Somehow, the scalding flush across Sans’ face made Grillby smirk in silent victory, even if it had likely been due to embarrassment. He felt the melodic ebb of the skeleton’s soul, achingly distant through the short space between them. It reminded the fire monster of their tender little moment and he relaxed, head held on one hand again. Grillby propped an elbow on the table, awaiting Sans’ next question.

“ok… so what does a star eat?”

Grillby hummed softly, _“Asking in such a way…”_ He paused in consideration, then gave in to a slight shrug. _“Suppose… hydrogen for most. Though, I personally enjoy curries and sours.”_

Sans’ eye lights grew brighter with interest and he leaned over the table, blatantly ignoring another notification from his pocket. “what about composition?”

The bartender gave him a quizzical look and didn’t answer, but he felt something flush just under his flames.

“i mean, magic and fire, sure. but you gotta have a little physicality like the rest of us, right? with me, a bit o’ bone, bit o’ dust, maybe some pebbles…” Sans grinned openly, making Grillby’s flames pique and tinge a shade or two of gold.

_“…Sans.”_

The skeleton grunted inquisitively, still grinning wide. He looked so pleased with his question that Grillby almost regretted the words that came out of his mouth next;

_“That’s… such a… personal thing to ask. Haven’t even had our first date.”_

He couldn’t resist. He couldn’t even stop the words from coming out, but there they were, lingering in the air as the heat came off his body like waves. Grillby paused as he saw a subtle shift in Sans’ body language. His confidence seemed to peel away in the seconds that passed, and Sans grew tense.

He had embarrassed Sans, and now his gaze was met with avoidance. Grillby released a soft sigh, wondering if an apology would make Sans more uncomfortable or just make things awkward. He offered an apologetic smile anyway and patted Sans’ hand before he got up to clear the table of dishes.

While Grillby was certain that he’d embarrassed his friend to the point that Sans remained in awkward silence, he was caught somewhat off guard when he felt a tug on his apron just as he intended to leave. Inquiringly, he looked over his shoulder to see Sans nervously grinning up at him.

“sh-should… probably fix that, huh?”

The bartender returned the grin as he reached to pat Sans’ shoulder in agreement, his hand trailing down his arm as Grillby left in a silent and playful manner.

Over the course of the afternoon, Sans eventually pulled all the components and tools back in front of him again. It didn’t take long for him to become immersed in the repairs, creating a small mess of crumpled napkins as he wiped the moisture from each piece before inspection.

Grillby caught brief glances as the afternoon steadily grew busier. Soon, Sans stopped looking out of his booth so much and remained concentrated on his work, only taking breaks to answer his phone. At some point, the fire monster noticed that the cell phone hovered in air, near Sans’ skull, while an assortment of delicate-looking tools poked out from Sans’ teeth. It appeared to be the only way that the skeleton could keep his hands free to fiddle with the mess of wires.

The earlier regulars eventually paid and left, and more customers arrived. Sans stayed for the entire afternoon. Intermittently, Grillby wandered from the other booths after taking away payments and dirty dishes, taking the route past Sans’ table.

Considering it after a few passes, the fire monster quickly stooped and deposited a soft kiss against the preoccupied monster’s skull. He couldn’t resist; he was surprised he had for this long. Grillby didn’t even turn to see the wreckage when he heard something drop and roll off the table as he continued towards the kitchen. If his patrons’ expressions and hoots were anything to go by, the kiss had its intended effect on Sans and Grillby had difficulty repressing his grin until out of sight.

If truth be told, Grillby wanted to do a little more every time, just to see how flustered he could make Sans. Just a gentle push, to test his boundaries. The second time, he found Sans hunched so far into his hood that Grillby was sure he’d suffocate.

So instead of a kiss, Grillby tugged off his right glove and flicked his index finger over the topmost vertebrae peeking out, moving away just as he witnessed a jolt of surprise shudder through Sans’ shoulders. His head whirled around, flooded with the hue of his magic. The sudden movement caused a few select tools and screws to skitter and roll off the table, and Grillby heard a soft gasp of protest as he walked away.

It was a satisfying exchange, if only a bit one-sided. He knew he shouldn’t, but Grillby relished the teasing. Every time he stole a glance the skeleton’s way, Sans was more or less avoiding his look, though his soul glowed so brightly that Sans was sure to draw attention to himself if Grillby kept it up.

Sans eventually finished with his repairs. He’d been in the middle of carefully packing away his tools when Grillby found an excuse to meet up with him again, smiling a pleasant smile as though Grillby hadn’t spent the entire afternoon ambushing him with fleeting touches and stolen kisses.

The subtle clatter of bones was muffled under Sans’ jacket as he approached, leaving Sans much more aware as the minutes stretched on from the last sneak-attack. If Grillby had to guess, his actions left the skeleton more flustered than he’d originally thought. Grillby carefully suppressed a grin, presenting a slight smirk as a peace-offering instead.

“g-gotta-” Sans started, then immediately ended what he was going to say. He swung his legs out from under the table, turning on the bench and shouldering his bag. He took strides not to look like he’d been avoiding Grillby’s face the entire time.

Grillby couldn’t help the tug at the side of his mouth; it was beyond adorable.

One last time. Then he’d stop.

_“Leaving so early?”_

Dumbly, the skeleton nodded, his gaze focused at the other end of the bar. He then seemed to realise something and the hue of magic in his face grew bolder. Sans’ gaze dropped to his knees.

_“And without paying.”_

Grillby noted the way Sans’ grimace tried to force itself into a grin and Sans’ hand automatically went to his pocket, likely in search of coins. When he predictably came up with nothing, the bartender closed the distance between them. Sans had no choice but to apologetically look up from his seat.

“wow, uh. may.. maybe put it on-”

Grillby carefully rested a gloved hand on both the table and the top of the booth’s bench, effectively trapping Sans where he sat with his body. His gaze flicked down to where Sans’ phalanges idly tugged at the drawstring of his hood, plucking at the aglets as he continued to grin uneasily.

“grillbz…?”

 _“Afraid payment is required upon service this time.”_ Grillby’s voice came out with a faint snap at the end like dry kindling popping, every word measured and slow. It was almost sensual.

“i’m good for it, g,” Sans shyly countered, looking far more frazzled for the implication. “if you let me go home, i can raid the couch-”

Grillby’s movement cut him off and Sans sat stark still. The fire monster leaned down, his face bare inches away and giving off even more heat as Sans attempted to continue;

“-and… come… back…” The last words died off rather abruptly, his voice soft and confused.

Another buzz sounded from Sans’ pocket, but they both ignored it. Sans didn’t move. His nervous trembling made it impossible for Grillby to hold back his grin for any longer. Seeing it, the tension in Sans’ shoulders eased and he even allowed himself to laugh.

_Bzz-bzzt!_

“you’re teasing me.”

_“Perhaps not.”_

Sans released a shaky breath, but he still hadn’t moved away. Grillby found that it had proved to be a little too much fun to stop just yet.

_Bzz-bzzt!_

“you’re really close, g,” Sans murmured, his voice lower.

Grillby moved his hands from the table and bench top to cup each side of Sans’ jaw, flooding the bone with warmth. He relished the way that Sans sighed in appreciation and his eyes seemed to automatically close in submission. Grillby was sure that any lingering cold that clung to him from when Sans came in, evaporated on contact and in his company.

_Bzz-bzzt! Bzz-bzzt!_

_“Worried that others will stare?”_

He lightly caressed Sans’ right cheekbone, his smirk quirking a little more when Sans just let him do it. There were a couple of giggles from the other side of the restaurant. Happy subdued yipping came from the canines until they were stopped, hushed by another regular. They probably wanted to see where this was going.

“th-they’ve been staring all day, boss, c’mon. you’ve been givin’ ‘em a free show,” was Sans’ attempt at humour. His voice sounded shakier the longer Grillby stayed close, and he kept his eyes closed. The fire monster idly wondered how long it would take for Sans to give in and zip away again, rewarding him with another victory.

_Bzz-bzzt!_

He appeared to be holding his own, though; not like that infernal phone, which kept buzzing in Sans’ pocket like a wind-up toy. Grillby ignored it, since Sans was content to do the same.

 _“Suppose I should let you go. However, not before I collect what’s due,”_ the bartender murmured as he leaned forward a little more.

Sans didn’t shrink away as his mouth brushed against the bridge between his eye sockets, softly caressing Sans’ face. The bone heated under his breath and furrowed slightly until Grillby left a kiss, feeling the oddly malleable bone relax under his mouth. Sans instinctively sucked in a surprised breath and his hands lay uselessly in his lap, but Sans’ mouth fell open with the lingering touch.

Then Grillby gave two more kisses on each cheekbone, one after the other. Grillby lingered long enough to feel a subtle quiver pass through the smaller monster.

Much to his regret, Grillby let him go, leaving Sans smiling wide and dopily like a stupefied fool. Grillby thought that would be the end of anything else -- until he heard a contented mumble from Sans.

“…should really pay for all my meals that way.”

When Sans left Grillby’s, his footsteps were sure, light and springy. His face burned with a flustered glow from all the hoots, good-natured laughter and teasing from the regulars on his way out the door. He’d even pulled his hood up to hide his furiously blushing face. It then dawned upon him that it was apparently a thing that mature skeletons could do; after all, Papyrus had displayed the phenomenon a time or two before.

He checked over his phone to see what all the notifications were for; three missed phone calls from Alphys. That was weird; normally she didn’t call.

Though the thirty waiting text messages were nothing new.

Alphys (Last message received: 3:09pm);

\- Oh! We got the feed!! Nice job! (☆｀・ω・´)ｂ  
\- I was a little worried since you were taking so long   
\- Not to say that I’m impatient! Just remember to keep warm. Snowdin’s cold, right? I don’t work well in the cold so you must be so miserable (╯︵╰,)   
\- Thanks again for helping me. It really means a lot! Orz   
\- Um… Σ(゜ロ゜;)   
\- (＊〇□〇)……!   
\- Hey, that fire monster?   
\- He’s pretty close   
\- I think he might,   
\- Σ ( Д )ﻌﻌﻌﻌ⊙-⊙   
\- SANS   
\- SANS THE FEED   
\- OMG I CAN’T WATCH THIS??? ヽ(＊>∇<)ﾉ   
\- SANS THAT FIRE MONSTER MIGHT *LIKE* YOU   
\- WHOA HOLD ON BACK UP   
\- WAIT IS ~*~*THIS*~*~ THE ‘SOMEONE’??????? (///º 艸º///)   
\- SANS, YOU OMG I don’t know what to say!!   
\- THIS is the guy!??! WHAT A CHOICE FOR A FIRST CRUSH LOLLL   
\- A fire monster! OMG. SANS. I’M SORRY BUT THIS IS TOO CUTE!! ♥   
\- HE REALLY LIKES YOU   
\- ~*~*REALLY*~*~ LIKES!!!!!!   
\- OH WOW OH GEE OH BOY (ﾍﾟ◇ﾟ)」♥ ~   
\- Hey, quick note Hotland monsters are VERY bold   
\- Like, incredibly. He is going to be M E R C I L E S S once he finds out you like him omg   
\- But I um… guess you know this by now???? HAHA oh man… AND I got a front row seat to you two dorks flirting!? XD   
\- I ship it!! Sans!!! I’m not going to lie!! This is too perfect and cute and SAJKHDFG!!!!!   
\- AAAAAAA MY HEARRRRRT THIS IS SO SWEET   
\- HE KISSED YOUUUU   
\- OMGGGG~ ・:*(〃∇〃人)*:・   
\- SANS!!!! You’re such a dork lmao I’m sorry (∗ᵕ̴᷄◡ᵕ̴᷅∗)՞ answer your phone~~~

Sans stood as still as a rock as he glanced down to the camera under his arm. The little red light on the side of the lens shined brightly, indicating that it was live. In complete abject mortification, he felt his magic spike and flood throughout his bones.

Without thinking twice, Sans quickly found a rift and put the peak in energy to good use, made a shortcut to the bush outside of the Ruins’ door and hastily stuffed the camera inside. All the while Sans glared into the lens and desperately hoped that he didn’t look as embarrassed as he felt.

**Notes for the Chapter:**

> Alphys' texts were literally me this entire chapter. Girl, stop making friend fics of people you know!!!!
> 
> Art I drew for this chapter (sfw) can be found on [deviantArt](https://www.deviantart.com/skerbb/art/Postcards-From-Waterfall-ch-16-817150494) and [tumblr!](https://skerbaderbadoo.tumblr.com/post/188415221847) :D


	5. Chapter 5

**Summary for the Chapter:**

> It appears that Sans makes a whole slew of mistakes today.  
> Midnight texting.  
> Biology lessons.  
> Wrestling.

Alphys (Last message received: 1:23pm);

\- SPILL THE BEANS 八(＾□＾*)

*no way aint a thing gimme the coords

\- Sans, this is kind of a big deal!! I’m sorry!

*nah how bout we get 2 work like what u asked bc this convo is suddenly terrible

\- WHO IS HE o(*>ω<*)o

*how bout we talk bout literally anythin else  
*im kinda bushed tbh   
*heh

\- I NEED DETAILS (＃´艸｀)

*dont  
*gdi alph u dont gotta make this a huge deal   
*sides im not givin u the deets 4 ur shippin charts   
*ys that even a thing   
*nvm dont ansr that dont wanna know

\- YOU DON’T UNDERSTAND  
\- THIS IS A ~*~*VERY*~*~ BIG DEAL!!!? ಠﭛಠ

*ok  
*well sure but lets get n ur thing then

\- My thing? o_o

*sure  
*u know   
*ur big obvs af n love w/   
*u know

\- 49°21’12.2”N 2°11’26.5”E

He couldn’t help it. Sans laughed outright and went over the coordinates for the next stop in his head. There was a sentry station in the forest that belonged to Lesser Dog. Since Papyrus was likely to be patrolling the area at that time, Sans came to the conclusion that he’d have to warp to the other end of the forest in order to avoid getting caught. If only his brother could see the amount of effort he put into being covert, then Papyrus wouldn’t always harp on him for taking as many breaks as he did. It was a pretty decent job.

He trudged along, finding a rift point that brought him directly into the thicket just before his brother’s tile and ice puzzle. He hummed nonsensically as he slid safely across, then went over to the station.

It took Sans a few moments to realise that the camera he was looking for was hidden under the roof, just out of sight. He also noticed that Lesser Dog was nowhere to be seen, but saw a mess of scampering footsteps in the snow leading into a nearby field. It must’ve been break time.

A few minutes after he’d pulled the camera down and set about repairing it on the sentry’s desk, his phone rang. Suspicious, Sans pulled it out of his pocket and glowered at the screen. Naturally, it was Alphys. He ignored it, knowing it would probably be more needling questions, and he continued his work.

His phone buzzed a few times with some text messages and he waited until he had finished his repairs before taking a look. There were four different messages, all with some variation of a smarmy text emoji with raised eyebrows. No further questions about his crush, though.

Sans messaged her back, asking for the next coordinates. It looked like that was the last of the cameras that needed repairs, apart from the one outside of the lab in Hotland. The mortification he’d felt earlier had died down to just plain embarrassment by the time he resituated the camera back in its proper place.

“BROTHER!”

Sans nearly dropped his bag in surprise. He turned his head to see his brother darting up to him from up the field, in the exact location he’d come from.

_Crap._

He hoped Papyrus wouldn’t have noticed where his footsteps suddenly started in the trees, but by the time his younger brother marched up to him, he looked far too elated to have noticed. Sans silently wished he hadn’t seen them, in any case.

“WHAT ARE YOU DOING OUT HERE? THIS IS DEFINITELY NOT HOTLAND.”

 _“ice_ to see you too,” Sans drawled, giving his brother a big grin. “alphys said it was _snow_ problem if i took a few to see my best bro.”

Papyrus’ expression shifted to one of mild surprise -- that is, until the puns dropped. Then he scowled, his teeth grating together. Sans grimaced at the sensation it likely made and unconsciously took a step back when his brother stomped closer.

“LOOK AT YOU! WHAT HAP-” Papyrus stopped, then glowered when he caught the unmistakable scent of grease and fast food. “I SHOULD HAVE KNOWN! GRILLBY’S. ALTHOUGH I DON’T KNOW WHY YOU THOUGHT A UNIBROW WOULD SUIT YOU. IT OBVIOUSLY DOESN’T.”

Admittedly, it took a moment for Sans to put two and two together before a fresh wave of embarrassment shot through him and he used his sleeve to wipe at his face. The fabric came back with soot on it and he felt flush at the reminder of the kisses.

It would appear to be the wrong thing to do, but he wasn’t thinking clearly. Papyrus was even more interested by the fact that his assumption was different to what Sans thought, apparently.

“just went for lunch.”

“OH?” His younger brother’s eyes narrowed daringly, looking smug. Sans didn’t like it one bit. “AND HOW WAS IT.”

“it tasted-” He should have known it was a trap, since Papyrus’ disdain for the dive was well known; why would he ask how it was? His sentence came to a full stop; “it _tasted._ paps, did y’know we can make tongues?”

“WHAT AN UNUSUAL OBSERVANCE TO MAKE, SANS.”

“i’m not hearing a ‘no’.”

“AND NOR SHALL YOU! OF COURSE WE CAN, WE-” Papyrus stopped again, then grabbed Sans’ shoulders and pulled him forward to look at him head-on. Sans attempted to give him an innocent look but his reaction was delayed and he looked somewhat pained instead. A dawning realisation came over Papyrus’ face and Sans sucked in a breath to mentally prepare himself for the next outburst. “OH. MY. GOD!!”

“pap, no.”

“NYEH HEH HEH! ‘PAP’, YES! COULD IT BE??” Papyrus gave him a knowing grin and Sans squirmed out of his grasp, hands going straight for his pockets.

“cool it.”

Papyrus continued to laugh, the noise bouncing around the area as his voice grew in volume. Sans shrunk away, attempting to find an escape from the already fully humiliating day; he did not need an addition to it. Papyrus caught his hood as he made to slink off with his bag before Sans could get anywhere near a couple of feet away, however.

“MY DEAR BROTHER. IT SEEMS YOU ARE LACKING IN SOME EXTREMELY IMPORTANT LIFE LESSONS. ALLOW ME, THE GREAT PAPYRUS, TO SOOTHE YOUR WOEFUL CONUNDRUMS!”

“we can literally do this any other time, bro,” Sans immediately retorted, feeling his magic tinge his face in horror. “i dunno why you’re makin’ out like it’s a big deal.” It really wasn’t a big deal -- not anyone else’s, anyway.

“OF COURSE. BUT INSTEAD OF YOU HIDING AND DANCING AROUND THE SUBJECT AT HAND-” Papyrus tugged him so Sans fell in step beside him, then released his hold once he was sure Sans wasn’t going to leave. “TELL ME.”

“tell you what?” Sans countered, genuinely confused now. What subject? He really hoped Papyrus wasn’t going to badger him now of all times about confessing. Because that had already happened; it was just a matter of time before he got the nerves, so to speak, to bring it up on his own. When he was ready.

“WHAT’S SO INTERESTING ABOUT THAT GREASEHOLE?”

Ah. Yeah, that. Sans inwardly groaned as he realised that Papyrus must have also seen him go the complete opposite way of Waterfall the previous morning. He coughed awkwardly.

“i, uh,” he looked everywhere but his brother’s face. “c-can’t find, uh…” His glance flicked upward, still grimacing. Even though Grillby had suggested the prank and this was the perfect opportunity to carry it out, he was tired, and at least Alphys would let up on the questions if he was falling asleep. He had to get away, as ridiculous as it sounded. “c-can’t find my whoopee cushion, y’know? thought i might’ve left it there.”

Papyrus’ expression went flat and he sighed loudly. “I KNEW THERE WAS A LACK OF FLATULENT NOISES LATELY!” He pressed a gloved hand against his face and shook his head. He really thought he was on to something then!

Sans allowed himself to relax a little. “uh, alphys is waiting, so-” Idly he made a check for his phone, which had a few messages waiting. That was lucky. Or was it predictable? “still got another day with her, i think. she’s gonna check over some stats and we still got some variables to look through.”

Papyrus was still shaking his head as Sans made another attempt to leave. Sans was again, jerked back by his hood and he had to restrain himself from swearing in frustration.

“WHERE IS…” Sans hunched down into his hood, knowing what was coming. “…THE ECHO BLOSSOM?”

“dunno,” Sans mumbled, tugging at his jacket with one hand as he avoided Papyrus’ look.

“YOU DIDN’T THROW IT AWAY, DID YOU!?” Papyrus sounded aghast and Sans looked at him helplessly. Then he simply shrugged.

“maybe i left it somewhere.”

“SANS!! THAT WAS… SUCH A CARELESS THING TO DO!” Papyrus sounded extremely disappointed and Sans couldn’t help but flinch at his tone.

“yeah, my bad,” he played along, his eye lights shrinking in his sockets and settling to the snow at his brother’s boots. “listen… text me later? i, uh… i gotta go. keep a lookout for humans, ok baby bro? keep safe. love ya.”

Whether it was because his brother was stunned over his little white lie or because he’d been quick, Sans was able to get away. He made his way back through the field to the tile and ice puzzle and rounded the corner, readying his magic for a shortcut. Slipping through a rift, he twirled on one foot to regain his balance on the opposite side, nearly tripping over a large red rock along the path to Alphys’ lab. Whether he was emotionally unstable, or he had simply used too much magic in one day; either way, he was beginning to feel it.

His phalanges barely rapped against the metal door of the building when the hiss of mechanics stopped him and the royal scientist reached past the door and pulled him inside. For a moment, the glare of Hotland’s climate had made the reflection off Alphys’ glasses a bright orange and if Sans didn’t know her any better, he would have pegged the expression as devious.

“i need a nap. i’m exhausted,” Sans muttered, sounding genuinely fatigued. He’d done more in a day physically than he had all last week, and he was mentally drained as well. He sighed and let Alphys drag him by the arm further into the lab, where she’d set up a sleeping area for him out of the blanket and pillow he’d used before.

Gratefully, he sunk down on the sleeping pile, ignoring her excited and bouncy stance as though in hopes that he’d open up to her. Instead, he dropped back against the pillow, intending to sleep.

“Um… th-thanks again, for helping me with the… the cameras, Sans,” she said after a long moment of hesitation. It seemed like she’d lost her nerve, or it was reserved for online social interactions only. When Sans only replied with a quiet drone of snores, she sighed and went through the bag to put her tools away.

For the majority of the evening, Sans slept dreamlessly. He woke briefly when the air conditioning turned off and the place heated up fairly quickly. His mind roamed to earlier that afternoon and Sans couldn’t help but grin to himself, curled up under the blanket in the warmth of both pleasant and awkward memories. He felt his phone buzz in his pocket and pulled it out to look at it. The current time was 11:46pm.

There were a few messages from Alphys from a couple of hours ago, and two were from an unknown number. Naturally, there were also several worrying messages from his brother.

Papyrus (Last message received: 7:34pm);

\- IT OCCURS TO ME THAT I MAY HAVE UPSET YOU.  
\- WHILE IT IS NOT MY INTENTION, MY DEAR BROTHER, YOU HAVE TO USE THAT ROBUST BACKBONE OF YOURS AND CONFRONT YOUR FEELINGS.   
\- FEELINGS THAT, I ADMIT, ARE A LITTLE CONFUSING. AND POSSIBLY TO YOU, TOO.   
\- SO I HAVE TAKEN SOME LIBERTIES!!   
\- YOU MAY FIND SOON, A CERTAIN SOMEONE MAY BE CONTACTING YOU.   
\- YOU ARE WELCOME.   
\- (LEGIBLE WINK)

Alphys (Last message received: 9:58pm);

\- Hey there, not sure how long you’re going to be sleeping! So! I just wanted to say if you’re hungry you can have whatever garbage that’s in the fridge (∗ᵕ̴᷄◡ᵕ̴᷅∗)  
\- ? Not saying it’s GARBAGE but um? Maybe you’d want something   
\- There’s still some cookies and some monster candy. You know where the chip machine is too…   
\- Oh! The code for it is 4827 if you want. I forgot to mention it before (*´∀｀*)ノ   
\- The variables came back negative again. If what you’re saying is true, your ‘shortcuts’ tend to dip the gridline inward and shift things around until you get on the other end   
\- I still don’t know what the 3 hour break was… or how you got stuck ♒((⇀‸↼))♒   
\- I’m glad you’re ok though! ♥   
\- Hope these don’t wake you… anyway, it’s late and I’ll probably be passed out at my computer upstairs by the time you read these ԅ(¯﹃¯ԅ) lmao

Unknown (Last message received: 11:42pm);

\- Hello. I’m not quite certain if I should be messaging so late. Is this Sans?  
\- Perhaps it is one of Papyrus’ pranks. I do apologise if you are an unintended participant in this joke. Good night.

He couldn’t help but send the screen a perplexed look as he scrolled back to his brother’s messages. Sans was unsure about the unknown sender but after a few minutes of listening to the quiet hum of the lab, he exhaled in resignation.

Unknown (Last message sent: 11:44pm);

*this is a sans whats shakin

Sans waited a few minutes until the backlight dimmed on his phone, then it eventually turned off. He wondered what that was all about. Eventually, he came to the conclusion that Papyrus had probably come up with his own ideas as to what had happened at the bar, though Sans secretly hoped said bar’s top gossips wouldn’t reach Papyrus’ non-existent ears.

Sans exhaled a deep sigh and rolled onto his back to pull the blanket up to his face. Huddled within the cosy cocoon of blankets, Sans stared up at the high ceiling. The fans in the tiles moved slowly, lulling him back to sleep. From somewhere far away, he felt his phone slip from his fingers and rest against his chest as he fell into a doze.

The sudden vibration against his sternum rattled him enough to jolt him awake, however. Blearily, he brought the phone up to his face, cracking an eye open as he flicked it on.

Unknown (Last message received: 12:04am);

\- If this is a Sans I know, that is definitely the exact response I’d expect to receive. One can practically hear your mumble through the words.

*ur slow @ typin u know that  
*sides am a v busy skele if u knew me like ur insinuatin ud know this by now   
*how many sansses u know bucko   
*whos the imposter   
*i gotta know whos tarnishin my good name

\- Now I know for certain this is Sans.

*ay cheers ya done good next round @grillbz on me  
*yknow if i ever run in2 ya

\- I’m certain we’ll see each other again. Especially if you come to Grillby’s.

Sans narrowed his eyes at that and he shifted a little more to get comfortable, scowling at the messages all the while as he held the phone over his face. As he awaited a response, he scrolled up to read the conversation once more.

Unknown (Last message sent: 12:08am);

\- Let’s play a game to see how long it takes for you to decipher who I am.

*ur layin it on thick bud thats the thing w/ txts u cant know unless they say  
*this telecom sys is gr8 n all but its got drawbacks

\- You haven’t made a joke once and seem very agitated. Perhaps I am the one who is being pranked?

*idk bro kinda sounds like u werent even sure who u were msgin  
*sides i just woke up   
*gimme a break the ol engines still turnin over

\- You use a lot of shorthand in your messages. I admit, I’m having a difficult time deciphering it.

*ya i get that  
*so who r u   
*are+you^ just fyi   
*ugh

\- I live in Snowdin.

*ok not the ansr 2 my q but  
*me 2

\- You are not here, however.

*nah  
*hotland   
*all hot n toasty @lab

\- Careful.

*nah its cool  
*n by cool i mean hot af i love it   
*its basically the best temp not gonna lie

There wasn’t any immediate reply to that, so Sans snickered to himself and got up. He stretched until his spine popped and all the worst kinks were out, then he got up to visit the fridge. He squinted against the bright light and read over a few of the containers inside; plum halves, ichi… something, some kind of candy he didn’t like, and some more puffy-looking buns littered the shelves in a haphazard mess.

He wasn’t in a mind to heat anything up, so Sans grabbed one at random and briefly read over the cooking instructions. With a shrug, he just unwrapped it and took off half of it in a large bite.

It was spicy -- then unbearably spicy and even _hot._ Sans’ magic absorbed it before he could spit it out, and he covered his mouth with a soft hiss. Once the initial burn was gone and he could detect the lingering taste, Sans shrugged and took another bite, this time smaller. It was a bit better to manage. 

Idly, he checked his phone and felt almost pleased when another message came in.

Unknown (Last message received: 12:24am);

\- You have my envy.

*u like hot so much y dont u come here  
*you+why^   
*u know what ur gonna have 2 learn the lingo   
*esp if ur wantin 2 msg me in the wee hrs

\- Suppose I should, but I have ties here.  
\- And an intriguing arrangement.

*well that doesnt sound suspicious @ all

\- Would you like a hint as to my identity?

*idk how coy u bein w/ me  
*wait is this red   
*cuz i told ya b4 sorry ab the wing   
*was accident

\- This only brings more questions. No, this isn’t Red.

*…………doggo?

\- Sans, please.

*well ok u got me  
*hint pls

\- HIP 24436.

Sans blinked at the screen. He had to admit that in whatever context this was in, he had no clue what it meant. It wasn’t an engineering term nor anything he normally came across. Nor did he think it was a boss monster, as being so forthright about HP levels was deemed unclassy in monster culture. Sans must’ve taken awhile to think about it, since the person on the other end deemed to clarify;

Unknown (Last message received: 12:46am);

\- I apologise. It’s difficult to parse the language through the phone. Is this better?  
\- β.   
\- If you need further clarification, I may be suitably obliged to offer further hints.

*wth thats not even a hint thats a gd fancy b  
*wait thats beta gdi   
*its like u like 2 see me squirm   
*reminds me of a guy i know

\- Ori.

*beta ori?  
*that an anime?   
*wait is this alphys   
*thought u were sleepin i can hear u down here girl   
*w/ ur betta ori himes

\- Sans. This is not Alphys. Should I offer another hint?

*aw she woulda liked that  
*2 jokes n 1   
*ok ya gimme another im just warmin up

\- Possibly the most flirtatious thing you’ve said so far.

Sans nearly dropped his phone but he managed to catch it in time, though he lost the bun in the process. He realised with that last message just who the unknown number was, and a whole new jumble of emotions flooded over him.

First, there was the strain of nervousness, because _holy hell, Grillby was texting him._ Then horror, as Sans had said quite a few callous and even compromising things about heat. Thirdly, he was irritated that Papyrus had guessed right as to whom his crush was when Sans had meant to keep it from him -- at least, for awhile longer.

Unknown (Last message sent: 12:49am);

*r u srs  
*pap took this 2 far   
*ur not jokin

_Help,_ Sans internally screamed.

Unknown (Last message received: 12:53am);

\- I can say that I’m honestly flattered.  
\- It’s not every day that someone tells you that they love an aspect of yourself when everyone else shies away from being burned.

Sans stood stock still and stared at his phone. If he had blood, it’d be draining from his face. Instead, Sans shook his phone and grunted as he pretended with all his might to fling it across the lab. Of course he didn’t, but it relieved some of the pent up tension.

It _was_ Grillby. Papyrus had given Grillby his goddamned number!

Unknown (Last message received: 01:14am);

\- I didn’t mean to be so forward. I’m unable to help myself at times.  
\- If you were serious this afternoon, I would be inclined to take you up on your offer.   
\- To fix our issue of not having gone out.   
\- If your reaction right now is anything like the other day, well…   
\- Do make sure to take care of yourself.   
\- After all, it would be a shame for you to come back to Snowdin not the least bit worked up.   
\- I’m at dangerous risk of jealousy.   
\- Heat is the best temperature, by far.   
\- Sans, did I scare you off again?   
\- Another point for me. Have a pleasant evening.

Flustered, Sans found himself just envisioning Grillby’s tone and the smirk that came with it. He scrolled up through the past messages, lamenting the things that he’d sent. He should’ve known. In hindsight, perhaps texting an unknown number in the middle of the night wasn’t exactly the best idea. Irritably, he brought up his brother’s contact information and typed out a response. Before he had the urge to hit ‘send’, Sans immediately deleted it.

No, he couldn’t do it, namely because Papyrus would know that Grillby messaged him, and Sans’ anger would only confirm his brother’s suspicions. Sans wandered back to the sleeping area and flopped down again, wondering if he could settle down enough to fall back to sleep.

Eventually, he did.

  
  


The following pre-noon amble by both Alphys and himself was mostly quiet, if not a little awkward. Sans made no mention of Grillby’s messages over his breakfast of sweetened coffee and jam toast. He was very proud of himself in that he managed to kick the chewing habit early enough before it got out of hand or was noticed by anyone else. So far, two hours into the day, it was going well.

Alphys eventually brought out the books she had promised to loan him, along with his gathered notes. Thanks to being in a cipher that they didn’t recall, they hadn’t helped much.

Meanwhile, Alphys’ cursory scan of his soul still felt intrusive, despite Sans’ efforts to remain calm throughout the procedure. She noted how his bones seemed thin, but it was only natural; Determination made monster physicality dodgy, at best.

The hours that passed were spent repairing the camera stationed outside of Alphys’ lab. If the one by the Ruins had been bad, Sans cursed the one he worked on then. It would’ve been easier to construct a whole new one, but Alphys was adamant that she couldn’t find the necessary parts on such short notice. It took the better half of the afternoon to finally get it working again.

Soon enough, it was time for Sans to go. Alphys thanked him and told him to take better care of his phone and that she wanted updates as soon as anything else happened. She didn’t mention if that was either due to his work or how his relationship would progress, so he didn’t say anything. Sans didn’t quite know how to address that line of thinking, so he just shrugged indifferently and waved goodbye on his way out.

Although travel was quick via his shortcuts, Sans felt apprehensive about Waterfall. The malaise he felt as he bypassed the entire area almost seemed to tug at him when his slippers met with the icy patch on the outskirts of Snowdin. He set his jaw as he peered down the cavern, but Sans shrugged off the worry, burying it until he got back to his house.

By the lights’ glow inside, Sans figured that his brother was home. He inhaled sharply to allow the crisp cold air to whirl around his bones, still quietly pondering the difference between hot and cold. Then, he crept up the steps to the door, poised to open it, just as it opened without warning. Sans’ bag slipped from his shoulder as he was yanked inside with a startled grunt, pulled into an energetic and tight hug.

“missed you, too,” he said, muffled against Papyrus’ clothes. He gave a couple awkward pats to his brother’s back, then was released, almost shaken as Papyrus took him by the shoulders to look him over.

“WELL?” His tone was expectant and Sans could only stare up at him with thinly veiled confusion. When he didn’t reply, Papyrus sighed quietly with all the patience of a saint. “OH SANS, WHAT AM I GOING TO DO WITH YOU?”

Noncommittally, Sans shrugged and dumped his bag onto the floor by the coat rack and wandered inside. “dunno what you mean, bro.”

Irritation momentarily flicked over his brother’s face with Sans’ lack of care as to where the bag and its partially spilled contents landed. Papyrus bent to retrieve the discarded items and stopped shortly, eyeing the titles of some very peculiar books.

Books that admittedly Papyrus hadn’t read himself, but he could guess the content to, anyway.  
 _\- Fathomable Resonances: An Inward Reflection to Maturation & Genesis _ by E. S. MadHob _  
_ _\- Biology of Magic_ by E. Creeper   
_\- Magical Bodies & The Housed Soul _ by Mathers _  
_ \- E/M FLUX BIOLOGY: New Home Collegiate 19xx Comprehensive Edition

He shot a sidelong glance to his brother and shouldered the bag while Sans got comfortable on the couch to watch some television. He then followed suit, sat down, then dropped the bag between them.

“I’M AFRAID I MIGHT HAVE-” Papyrus grimaced, not caring to admit his mistakes to the point where it would likely be regarded as suspicious behaviour, but he soldiered on. “-NOT CLEARLY UNDERSTOOD YOUR PREDICAMENT, LATELY.”

Sans turned his head the barest fraction to indicate that he was listening, but his gaze never strayed from the television. He was bunched up on his end of the couch with his hands firmly rested in each pocket.

“SO… WHAT I WOULD LIKE TO OFFER IS-” Papyrus grimaced again and straightened his back to sit upright. “-AN APOLOGY. FOR I WAS INCREDIBLY RUDE.”

That got Sans’ full attention. He turned on the spot, perplexed as Papyrus stared him down. Then as Sans considered it, he rolled a shoulder uneasily as though the notion was conflicting.

“nah, i was. sorry, guess i just got excited.”

“YOU SHOULD BE!! EXCITED, THAT IS, NOT SORRY.” Sans gave him a pained expression and Papyrus groused at him further. “DO YOU KNOW WHAT THIS MEANS??”

Sans had a feeling he knew what Papyrus was getting at, but it didn’t make him any more prepared for the contents of his bag to be completely upturned on the couch between them. Sans watched it all with relative calm, but bit any gnawing suspicions away as his brother read the books’ titles aloud.

“REALLY, SANS. THESE ARE TOO… WORDY.” Papyrus squinted through a bit of the text of _E/M FLUX BIOLOGY_ before setting it aside. “I KNOW WHAT YOU’VE BEEN GOING THROUGH! IT IS SOMETHING THAT YOUR GREAT BROTHER IS NO STRANGER TO.”

“pap, no.”

“AGAIN, TO THAT I SAY YES! ALLOW ME TO INSTRUCT YOU ON THE FINER POINTS OF MONSTER BIOLOGY AND INTIMACY.”

Mortified, Sans’ face froze into a state of shock.

“AFTER ALL, I AM VERY GREAT. AND A SUBJECT LIKE THIS MUST BE BROACHED _CAREFULLY_ TO AVOID UNNECESSARY EMBARRASSMENT!”

Oh no. This was _not_ happening.

“IF YOU PREFER, I CAN INTRODUCE YOU TO A FEW BOOKS AT THE LIBRARY. I HAVE A GREAT DEAL OF THEM MEMORISED, NATURALLY, IF YOU PREFER I DICTATE THEM TO YOU!! I ALSO REMEMBER THAT SONG ABOUT THE GNATS AND THE SEEDS THAT YOU PICKED UP!”

Sans sputtered incoherently, his confusion and horror only building at a rapid rate to a full crescendo. It left him parroting what Papyrus said like a half-brained idiot. “gnats… and seeds?” He probably shouldn’t have repeated that. In fact, it came to him quickly enough where this terrible conversation was headed. “no-”

“YES!! AFTER ALL, I HAVE A VERY GREAT MEMORY. AHEM-”

As quickly as he was able to, Sans got up and tackled his brother off the couch, interrupting the first word of the lyric with a startled exclamation. The song was along the lines of maturation and mating, drawing parallels between mushroom gnats bringing echo flower seeds to different areas of Waterfall. The only thing was that it was meant for _children._ Sans definitely was not its intended audience.

“SANS!! THAT WAS ENTIRELY UNNECESSARY!!”

“don’t you _dare_ sing that-” Sans huffed indignantly, but allowed the rest of his sentence hang. Papyrus gave him a playful shove and pushed him to the floor; it was payback for upturning them both from the couch. Sans attempted to crawl to his feet, but his brother kept him from going anywhere.

“WHAT? ARE YOU HAVING A BAD TIME, BROTHER? DO YOU THINK YOU ARE TOO _COOL_ TO BE SUBJECT TO ONE OF THE GREAT PAPYRUS’ MASTERFUL LECTURES ON MONSTER BIOLOGY? JUST BECAUSE YOU’VE IGNORED YOUR BODY FOR YEARS, AND IT’S FINALLY HAPPENED-”

Sans groaned as though in pain and struggled to get out of Papyrus’ grasp. Defensively, he laughed and desperately elbowed Papyrus in the ribs to get him to release him.

“get the hell off of me, pap, i swear-”

“YOU SWEAR ENTIRELY TOO MUCH!” Papyrus thundered, unable to suppress his vicious grin. “BUT NO, YOU’RE NOT GOING ANYWHERE! YOU’RE NOT HIDING IN YOUR ROOM! YOU’RE NOT GOING TO GRILLBY’S! YOU’RE GOING TO SIT HERE MANO-A-MANO WITH ME AND HAVE A MEANINGFUL, SCHOLARLY CONVERSATION ABOUT _FEELINGS-”_

“oh my god, pap! _no!”_

“-AND CANOODLING-”

“argh!” Sans attempted another kick to crawl out from his brother’s grasp, desperate to get away from the conversation.

Papyrus strengthened his hold around Sans and pulled him close to wrap his arms around his rib cage. He strained when Sans retaliated by using force to push his skull away with both hands. “-AND COITUS! AND COPULATING! AND COURTSHIP!! NYEH HEH!!”

“stop saying those words!” Sans seethed from between half-formed, strangulated noises.

“WHY? THEY AREN’T BAD. JUST LIKE THE WORDS ‘MATING’ AND ‘BREEDING’! UNLESS YOU’RE THINKING OF THEM IN RELATION TO THE WOOING OF A CERTAIN-- _OOF!”_

Sans successfully managed to shove his brother onto his back and wriggle free from the assault of torturous words. His face was flushed a bold cyan hue from what Papyrus was implying. It was just so awkward, so increasingly embarrassing that he just _had_ to escape.

Though, if Sans was being honest with himself, he’d realise that the words only made him uncomfortable because it was likely that he _was_ associating it with a certain other monster.

_Shit._

“‘FORNICATE’ ISN’T A BAD WORD EITHER, BROTHER,” Papyrus smugly called up from the carpet with a laugh.

Sans pulled the drawstrings of his hood to hide his face, unable to stop another pained groan as though every embarrassing word chiselled away at his remaining HP. Huffing as he got up from the exertion of the struggle, Sans flopped down onto the couch next to all of the books. Even though he had wanted to escape, he didn’t want Papyrus to think that this kind of jape was funny.

“fine,” Sans wheezed and adjusted his hoodie with a pointed glower. “but only ‘cause you’re right.”

“NYEH HEH HEH!! OF COURSE I AM! THERE WAS REALLY NO DOUBTING THAT.”

Papyrus beamed and scrambled off the floor so he could instruct with a little more care and a little less volume. Sans curled up with his face covered by his hands on the opposite end of the couch during Papyrus’ entire lecture, and he regretted allowing his only chance to escape slip away.

It was his own fault, he supposed. All those years teaching Papyrus things would’ve been easier to retain had he only cared for his _own_ education. But no, now it was Sans’ turn to sit down and learn from his younger brother. Things he should’ve learned, but didn’t because they weren’t things that would happen to him. At least, that he _thought_ wouldn’t happen, as he’d been specifically told as much. It would’ve been easier than _this._

It was just humiliating.

Admittedly, Papyrus’ lesson was only for a couple of hours and very thorough for what knowledge Papyrus had, but the whole thing felt like Sans had reverted to his stripe-wearing days. Lamentably, Sans could only slowly shake his head in his hands after a brief explanation on how various monster babies were formed -- now with his brother’s hot new take on how it ‘should be’ or ‘could be’ between different subsets of species. It rendered Sans utterly speechless.

There were just _no words._


	6. Chapter 6

**Summary for the Chapter:**

> Sans gets a postcard. A FIGHT between him and Papyrus destroys an item box, which he now has to fix. Sans gets a little closer to the universe. (audible wink)

Sans stared into the fridge.

His gaze was hard, his grin set into a rigid line. He went over one or two things in his mind. One; his brother’s obsession with spaghetti was getting out of hand, and two; it was becoming increasingly difficult since his development to hold off on eating any of it. It was a good thing Papyrus wasn’t home while Sans agonised over the decision to even  _ try. _

Those long noodles. The thin sauce. The peppering of oregano that smelled good at first, but then just simply overpowered anything it touched. And why was there  _ sage?? _ Sans had a feeling Papyrus would one day accomplish something edible, but that time clearly wasn’t now.

Sans drew himself up and closed the fridge door with a little too much force to peruse the cupboards instead. Noodles of every variety, glass jars of sauce, dried herbs and spices that his brother just didn’t know how to use filled their pantry. Idly, he wondered if Papyrus’ taste was just shot. It was a mean thought, one he felt guilty for immediately, naturally.

He’d been avoiding Grillby’s restaurant. It wasn’t as though his food didn’t taste good; it tasted  _ amazing. _ But Sans had become overly petrified following his friend’s first covert messages. There was a time or two when Sans had to correct himself whenever he jolted in surprise, realising that it had merely been his phone notifying him of incoming text messages.

He found that the messages were a little strange. It was obviously a way to keep a running tally. 1/0. 2/0. 2/1. 3/1. The question mark he sent back wasn’t met with any clarification. Somehow, it made Sans a little uneasy. The unknown always did that to him, although this was for an entirely different reason altogether. Sans quickly added the number to his contacts after that so it said ‘Grillby’ instead.

The second reason why he avoided the bar and its owner was because he’d been feeling irritated lately. It had actually spurred an impromptu sparring session with Papyrus that left Sans more exhausted than he’d ever felt before. His magic was going haywire and after his nap, Sans felt like he needed to burn the extra accumulation off. Yet after he did, he regretted it.

  
  


Today was a marked repetition. Sans left home into the snowy street and once more bypassed the restaurant, making that a total of 4 days since Grillby’s last personal encounter. He beelined straight to the cosy little shop beyond the trees and his neighbours, taken to the sweet little thing waiting for him inside.

The chimes rang as Sans pushed the door open, grinning so wide it looked almost painful. The shopkeeper, Bonnie, was behind the desk in a large blue corduroy chair as she worked on her knitting, and she simply waved to Sans when he stamped the snow from his feet.

“hey, sweetbuns,” Sans whistled as he shuffled over to the display counter. “missed ya.”

Bonnie’s brow arched sardonically at the greeting and simply held out her furry hand over the counter expectantly. Sans tisked quietly, rummaging into one pocket for the required amount before carefully dropping two larger coins and a smaller one onto her palm.

“You two, some days, I do swear,” the lady sighed as she put her knitting away and got up. “Startled me half to Home with that ruckus the other day!”

“my bad,” Sans replied automatically, his grin tightening and his tone not at all apologetic. His gaze settled on the bunny as she pulled out a cinnamon confection from behind the case, still oozing with warm icing: the complete embodiment of indulgence. With practised ease, she slid it onto a plate, as Sans never strayed far enough to merit wrapping it up. He always ate it on the spot.

“I’m still wedging bones out of the roof tiles,” she groused, her voice prim as she slid the plate over the counter. Then she turned and sunk back into her chair. “Completely decimated the dimensional box out front! Whose are they?”

Sans gave a half-hearted shrug as he took a big bite of the gooey bun, instantly gratified for coming here. “probably mine.”

“Reminds me of my oldest,” she mused, half-smirking to herself. “They can’t manage their magic yet either. I’m still finding pine nuts and swathes of half-constructed fluffs ‘round the woods out back.” With an air of finality, she sighed, the heavy tone that only a mother with children still in training could produce.

Sans stopped mid-bite to regard her and analyse the sentence. Her assumption was that… he was still learning to control his magic? Sans wasn’t sure how to respond to that, but he caught her curious look. Regardless, Sans kept his expression as neutral as he could, even though something twisted inside of him at the notion.

“It’s good of your brother to help you, at any rate.” Her tone was not judgmental, a saving grace considering how uncomfortable Sans suddenly became during their idle chit chat.

A thought came to him as the conversation wrapped up and he left the shop. He eyeballed the evidence of his and Papyrus’ skirmish a couple days past, now feeling particularly chagrined.

He recalled their little skirmish in the street, Papyrus’ laughs triumphant as he showed off a bullet pattern that he’d been practising. Sans actually made an effort to dodge, regardless of how precise and careful his brother’s attacks were when it came to him.

Sans’ magic was restless and unheeding lately, and the exaggerated movements felt like it helped somewhat. But it felt as though it wanted to branch out, coil around things and  _ move. _ Even as he moved, Sans could see the wisp of cyan and yellow streaming from the left side of his vision.

“SANS! SLOPPY FOOTWORK!!” It was probably meant more as encouragement than criticism, but Sans couldn’t help but draw parallels between certain dream sequences and the strife at hand. To say he was distracted would be an understatement, and the ice was doing its fair share of fighting too. “THIS IS WHY NO ONE BELIEVES YOU’RE THE OLDER BROTHER! NYEH HEH HEH!!”

“think fast, babybones!” Sans hollered over the thrum of crackling magic, conjured bones spiralling around his fist in unison. Sans raised his left hand above his head, his eye flickering briefly as he sent out two bones in a boomerang arc towards Papyrus.

In retaliation, Papyrus swung a femur-shaped mace, the crack of bones echoing through the street like a loud snap. Sans’ attack lurched off course and wedged itself into the side of the shop’s roof with a loud  _ thunk, _ and a fair amount of snow slid off it like a miniature avalanche. Sans had been pretty impressed by the deflection.

A small crowd had formed. As normal as it was for kids to be sparring amongst themselves, the skeleton brothers were anything but children. Sans’ breaths had reduced to hard pants as his slippers skid to one side. The only reason he had dodged Papyrus’ attack was due to his brother’s perfect control.

Sans focused on his brother’s turn, his grin tight and sweat beading on his skull. Papyrus was cool, showing all the bravado of a confident sparring partner as he conjured another set of bones, this time tinted cyan.

Dramatically, Papyrus aimed one of them at Sans, who skidded when he felt the sudden familiar weight of Blue magic pull him downward. Sans managed to resist with a grunt, but ended up in the snow anyway. Apparently his failure was hilarious and his brother’s triumph was cheered by a couple of kids’ laughter.

“cheater!” Sans huffed over the whooping of the crowd.

“NYEH HEH!! YOU’RE BLUE NOW!” Papyrus theatrically revealed, his fingers twisting in a waved arc that closed into a fist. Some starstruck kids in striped shirts looked up at him as he summoned more bones.

Now that a small crowd had started to egg them on, Sans grinned tightly through the pressure around his soul and pushed back with a bit more effort. It had soothed his recoiling magic a little, but the lashing flares were still present, like Sans wanted to kick back.

He was tired, but Sans knew that he needed to expend a little more energy. Just a few more moments of Papyrus’ specialty-choreographed attacks and he could take it easy.

Keeping traction in the snow was the difficult part, especially when Papyrus’ attacks burst out of the icy street in two jagged lines. Bracing himself for their approach, Sans grabbed a hold of a pair closest to him and they immediately stopped. He pushed his weight against the bones and lurched upward. There was an opening, an easement present for just long enough for Sans to clear the manifests. He knew it’d been Papyrus’ doing, but it still felt good to clear it.

As Sans twisted his body in the air, he flicked his gaze around to make sure no one would be hurt by the energy beneath him when he dropped to his feet. The landing had hurt him a little more than he thought it would. Sans grimaced as he was sent to one knee but his HP didn’t budge. That was another plus to sparring with his brother; he was always extremely careful. He was  _ just _ that cool.

“POOR LANDING, SANS!” Papyrus taunted loudly as he twirled a long bone in each hand for show. Sans had slipped and landed on his back, a pained swear at the ready. He huffed in short gasps, his magic heating the air around him enough to produce steam like true breaths. “GET UP. LET’S TRY IT ONE MORE TIME!!”

Sans grunted as he did what he was told. He slid again as he attempted to regain traction even with the Blue magic holding onto his soul. He gathered what he could of his wild energy, control slipping through his fingers like heavy cyan drops. As he gestured in front of him, everything seemed to still for a moment.

Sans could only use his left hand for attacks, pouring everything he had outwards. Though he had use of his right hand, it did nothing as far as controlling magic was concerned. It hadn’t for the longest time, so he kept it stuffed into his pocket, tight and ready to maintain his balance. It was easier that way.

Every pinpoint of magic that fell to the ground erupted into a wall of bone, calcium towers of varying heights and distances heading his brother’s way. It closed in on Papyrus in a combined path, like a tight maze that Papyrus would have to dance through in order to avoid being pummelled. Sans’ attacks would never hurt him. Papyrus was strong and sturdy, and Sans’ damage output was extremely weak. It wasn’t like he’d ever muster any intent to harm him, anyway.

After the snow stopped flying, Sans gasped against his sleeve, feeling how the heavy density around his soul eased once more. It thrummed hard, excited and active with the strain of magical adrenaline. He heard Papyrus cough and Sans trudged over to help pull him out of the snowbank he’d been buried in.

Everyone else had backed off during Sans’ attack, but they were now looking at each other and discussing techniques. A few from the crowd were inspecting what was left of the dimensional box between the shop and inn, reduced to an empty vessel of splintered wood and broken hinges.

It was only when Sans collapsed back into the snow with a tired laugh that they decided to disperse. Papyrus, eager to get going, tugged at his arm. It had gone well, apart from some property damage, and Sans looked and felt a lot less agitated.

Brushing the snow off himself, Papyrus pulled his brother up and over his back to carry him home. Overall, Sans had lasted 9 turns. Not great, but he’d beaten his previous record, and Papyrus couldn’t be prouder!

A beaming pinpoint of light had brought Sans out of his brief doze. Upon closer inspection, he realised that half the bar had emptied out into the street to watch from a distance, and that Grillby was amongst them. The flicker of his flames seemed curious but as always, it obscured his expression. There was something else there, but Sans found he couldn’t quite look at him for too long. It made his magic rile up again and there was absolutely no chance that Papyrus would drop him off.

Much later, he received a text from the bartender: 3/2.

After having settled down and eaten a good cinnamon bunny, Sans now felt the need to  _ not _ draw attention to himself in public. So he wandered off towards the forest, still peevish. The further out he went, Sans could see the reflection of his magic bounce off the snow and ice.

As he walked, he reigned in the near-chaotic flow of energy, focused on the task as he maneuvered around his brother’s puzzles. Sans could overhear said monster in the distance, giving a full-on speech about puzzle etiquette to some passerby he didn’t quite recognise. Since Papyrus was distracted, Sans decided to take a shortcut directly past them, deeper into the woods.

He found that using his shortcuts eased him a little more. While Sans’ magic coiled restlessly around his bones, he found rifts and exploited his shortcuts to get far away. He figured that he was probably miles away from town, far from the entrance to the Ruins and out in the dense thicket. It’d be the perfect area to let off some steam.

He heard his phone buzz in his pocket and quickly checked it.

Alphys (Last message received: 12:53pm);

\- Jumping around? (〃ー〃)

*ya been antsy lately need 2 burn off a few   
*this is rly weird not gonna lie

\- That’s ok!! I thought maybe something happened and wanted to make sure you were fine~   
\- You’re out pretty far (ノ′Дヾ)

*thx for lookin out 4 me just got some buildup   
*so weird

\- You haven’t read any of those textbooks I lent you yet??

*im a p busy guy   
*also no but also ya kinda flipped thru maybe 3 pgs   
*got a crash course from pap fisticuffs mightve been involved   
*mightve broke a few things will have 2 fix a dm box

\- Sounds like you “might’ve” caused some destruction… Honestly! You MUST keep a better hold on your magic and try to control it!!   
\- Now that ~*PUBERTY*~ is your deal now!! LOL (ღ˘⌣˘ღ)   
\- ✧･ﾟ: ✧･ﾟ: ･ﾟﾟ･:.｡..｡.:ﾟ::✼✿ [ Puberty Start !! ] ✿✼:*ﾟ:.｡..｡.:･ﾟﾟ･ :･ﾟ✧:･ﾟ✧

*gdi w/ the p word ur a real stand up chameleon

\- (￣︶￣;) Wow…

*like its flarin up somethin horrible dont remember pap bein this bad   
*just gonna blast the side of the mtn til im tired nbd

\- Sans, maybe you should actually try bringing a book with you next time???   
\- Reckless magical expenditures will only make it WORSE!! Ignoring it will too of course but you really REALLy ought to brush up on your bio lessons (꒵꜅꒵)   
\- Otherwise I will come over there and school you myself!!! (*´∇｀;*)

*girl u cant even stay here 4 more than 2hrs w/o turnin in2 a bicicle

\- I can probably manage… a few hours, yeah. I’m 60/20/12/8 so I wouldn’t dust, but Snowdin is TOO cold~ (¤﹏¤;)

*o great composition #s i love those   
*can u tell im rly excited bout learnin those

\- READ. THE BOOKS. SANS. ༼ ༎ຶ ෴ ༎ຶ༽

*i mean 60s magic i got that but   
*hey i resent that i read 3 whole pgs

\- After your pew pew parade I mean!! GOSH………

*ok better geckoin then

\- (；一ω一||)

  
  


The better half of the afternoon was spent summoning every attack he could muster. The bone constructs were denser than what Sans normally formed against Papyrus, but his damage output was so low the snow merely nudged off the inner side of the mountain into heaps in front of him. It made a lot of noise, echoing around until he was sure his harsh breathing would give him away more than his actual barrage.

Sans later found a shallow field of snow to lie down on, shrugged up into his hoodie like it was the fluffiest of clouds. It was cold, but it was a dry cold, one that didn’t stick to his bones or attempt to hide in his joints. He napped for awhile, unable to stave off his weariness. Napping had become such a quintessential part of Sans’ life that he barely had to think about it anymore. His saving grace was that there were no dreams lately.

The way back through the forest was longer, but Sans used shortcuts to keep himself alert enough until he reached his sentry station by the Ruins’ entrance. He wandered over, his footprints the only pair leading up to the massive doors since his last visit.

He knocked. Naturally, there was no answer, but it didn’t hurt to periodically check. It just felt like something he  _ had  _ to do.

Eventually, he found his way back to Snowdin. It had looked like the mail had been delivered, and the red flag on his mailbox was standing tall. Sans stared at it for a moment before he peeked inside, suddenly and oddly apprehensive. After all, checking the mail wasn’t something he normally did; that was Papyrus’ job.

A postcard. Its front was an old glossy polaroid with creases throughout. The image was blurred with water damage and faded to the point where only a few vague orange lines were visible. Curiously, Sans turned it over, only to have his grin drop by what he saw.

More cipher. He was running across it more and more lately. Sans couldn’t really remember the symbols, though quite a few of his notes were in the same script. As he looked at it, nothing came to mind apart from an unsettling twist in his soul. He wondered if it was even  _ meant _ for him…?

Regardless, he took out his phone to message Alphys to see if she could help him decipher it. They’d gotten nowhere with his old notes, and forcing himself to transliterate made Sans’ head ache.

Alphys (Last message received: 4:13pm);

*hey alph need u 2 translate   
[ ]

\- I’m not seeing anything? (꒵꜅꒵)

[ ]   
*ok now?

\- You’re not sending anything!! ლಠ益ಠ)ლ

*its a gd postcard

\- What does it say?

*idk its n dings   
*w8 i mean cipher idk y i typed dings

\- It’s honestly not showing up for me (┳◇┳;)

She sent a screenshot of his messages and there were blank spaces where the photo should have been. Sans scowled at his phone, then to the postcard, then held it in front of his face for a ridiculous selfie and sent it her way.

Alphys (Last message received: 4:17pm);

*what ab now

\- That is… probably a photo!! (-、-)

*gdi maybe the camera fried   
*thought u fixed it

\- I only added video feed??? The camera worked fine when I checked!!

*lemme try somethin hold on

Though he wasn’t sure why he thought it’d help, Sans snapped a photo of his front door and sent it anyway.

Alphys (Last message received: 4:19pm);

\- Nice wreath LOL   
\- Guess your camera works?? ???

*ok now lemme try again

This time he lined up the shot with only half of the postcard in view.

Alphys (Last message received: 4:20pm);

\- Uhhhhhhhhhhhhh

*ok hows it look

\- Uhhhhhhh…. ┐(´～｀)┌

*brilliant dr alphys great deduction knew i could count on u

\- It’s… glitchy? Like some broken VHS tracking bleed?   
\- I can’t make anything out though (´ж｀;)

*ok well thx 4 the help

\- Sorry （；￣︶￣）

Frustrated, Sans huffed a sigh and shoved his phone back into his pocket before he decided to head back inside. He briefly visited his room to grab his key so he could go behind the house and downstairs where he kept most of his college and CORE notebooks. It took Sans awhile to rifle through the drawers and cupboards, but ultimately found what he was looking for. Unceremoniously, he spread the few bursting binders onto the floor to study what information he could glean from it all.

It occupied Sans enough that he lost track of time. It had to be hours before he got another message from Alphys, just reminding him to read over his biology books. Sans didn’t bother to give her a reply.

He rubbed at his face. His skull felt as though someone set up a chalkboard inside of it and had started to scratch down the length of it. He just couldn’t focus anymore -- and he didn’t get any headway into understanding the cipher, either.

_ Dings. _

Why did that come to mind?

With his eyes closed, Sans tapped his pen between his teeth in thought as he went over it for the thousandth time. There was a piece of his memory missing, although when Sans looked deep enough, he could see holes everywhere. The reasons he went to college. How he understood Hands. Who had raised him from infancy. What had happened to their parents. Why was he alone to raise Papyrus, although his soul felt a little heavy at that last one.

Though the silence of Sans’ lab was usually comforting, it was starting to get to him now. That, and it was freezing, having no heat. Distinguishing the differences between temperatures was an uncomfortable notion, to say the least. So in order to escape the chill, Sans gathered up what he could along with a notebook to write in, and left for Grillby’s.

That should clear his head. Besides, thanks to his little outburst in the woods Sans was starting to feel a little better.

To his mild dismay, when he arrived Sans found Grillby’s restaurant filled to capacity. He glanced around the bar; his usual seat was occupied, all the canine unit’s tables were filled and there was only one booth left in the very corner of the bar. It looked recently vacated and lonely near the silent jukebox. The entire place was noisy with loud chatter, and along with Grillby’s ambient glow, the space was filled with a comfortable heat from everyone around.

Sighing softly, Sans moved past all the bodies and towards the only space left. His notepad, the postcard and the small green pocketbook were dumped onto the table as Sans took a seat.

He stole a covert glance at Grillby. The fire monster had his back turned to him, but he looked busy; it was possible that Grillby didn’t see him come in. So Sans shrugged to himself and pulled open his notes, working his mind and sketchy memory over to figure things out. The voices around him were a constant hum, punctuated by silverware clinking, barks and laughter. The atmosphere was soothing and Sans was able to focus better than in his basement.

It had been quite awhile. Sans lost track of time, so it could’ve been either minutes or hours since he had sat down. He’d tried to copy a few of the symbols down, as rusty as his imitation was. Intermittently, he glared at the postcard he’d brought along, studying the worn glossy front. Then Sans let out a heavy sigh and flipped it over to examine the back of it.

_ “Here,” _ a familiar voice whispered from over his shoulder.

Sans nearly jumped off the bench and turned his head, realising that he’d tuned everything out. The fire monster smirked at him and Sans felt an aching throb in his soul when he looked down to Grillby’s hand. He was pointing to one of the symbols in the green notebook.

_ “This one looks like-” _ Grillby made a sound that Sans didn’t quite understand; like an ethereal hum with an echo. Something musical, but not quite.

“uh,” Sans started quietly, staring at the fiery hand that lingered quite close to his own. “didn’t catch that, boss.”

Grillby chuckled quietly and gently plucked the pen from Sans’ grasp, leaning down so his body was hanging over him. His closeness made Sans a little flustered, but he let it be (since it was probably unintentional) as Grillby pulled a sheet of paper from his opposite side. Sans was so rapt by the motion that it felt like the glide of the pen moved over his bones instead of the paper when Grillby carefully drew out a symbol.

_ “It looks like this?” _

> [ ☄ ]

Recovering from the bare prickle that crept up the back of his neck, Sans leaned forward to peer at it. It looked like a small circle with three rods sticking out of its upper right side, all angled perfectly. It actually looked very similar to one of the symbols that he’d been studying, only the one in the pocketbook had 8 lines around the circle’s centre, equally spaced apart.

“you know dings?” When Sans spoke the word, there was another strangely familiar pulse at the back of his mind, something he couldn’t put his finger on. He looked up to Grillby, a little confused by the hang-up.

Grillby tilted his head and his fire crackled along his brow as though in curiosity.  _ “…Who is dings?” _

The enquiry made something twinge within Sans’ soul. He grew silent as he mulled it over. “yeah…  _ who…?” _ Sans muttered, not really sure what to ask. Was it a ‘who’, and why did Sans feel like that might be it? It was peculiar and even a little distressing that he couldn’t recall even basic information for the memory.

_ “Someone you know?” _ Drawing back, Grillby watched Sans, who appeared extremely distracted.

_ “is  _ it a someone…?” Realising a little belatedly that he was beginning to sound like an echo flower, Sans stopped and rubbed over his face with both of his hands.

_ “Had only assumed. You don’t appear to be sure.” _

“my memory’s not so great,” Sans replied quietly after a pause.

Grillby shifted where he stood, recognising that Sans was uncomfortable. There was something else hidden there but Grillby couldn’t be sure what it was.

_ “I’ve… known you for far too long to believe that, Sans,” _ he offered quietly. Sans only nodded slightly, his eyes averted and away from him. Grillby wondered if Sans’ brief absence had anything to do with the skeleton’s current mood.

But Grillby was unable to probe any further when he noticed that a few patrons were looking at him expectantly, even more gesturing for him to come over. With a quiet sigh, he patted Sans’ shoulder with a murmur that he’d return when the dinner rush had been dealt with.

Sans was still poured over his work by the time Grillby returned. He had an exhausted look on his face that made the fire monster’s soul twinge with pity. The blank pages scattered across the table were now scrawled through, more symbols copied down and some diagrams drawn that involved a lot of straight angles and calculations. The margins were covered in quite a few frustrated scribbles as well.

_ “…No luck?” _ Grillby enquired as he took a seat directly beside Sans. The skeleton shifted so the bench could accommodate the two of them, and the fire monster could see a subtle flutter of magic peek from under Sans’ collar. Despite how tired Sans looked, it was a little more energetic than what Grillby was used to seeing from him.

“i dunno where to start with this, but that letter you wrote  _ does _ look familiar.”

_ “Is it helpful?” _ Grillby couldn’t help but be pleased at that. He leaned an arm over the tabletop and propped his hand against his face to watch.

Sans was thoughtful as he turned to face Grillby, then he seemed to relax a little. “yeah, actually,” he revealed, sending Grillby a slight grin. “what are they?”

Grillby leaned in a little closer, unable to help himself. His fire fluttered briefly as Sans seemed to just  _ then  _ come to realise how close he was, and Grillby was able to witness the subtle way the cyan magic bloomed up from under Sans’ hoodie. As though Sans was made painfully aware of it, the bloom faded as he reined in his magic, resulting in an awkward grin.

Silently, Grillby smirked in triumph as his arm brushed against Sans’ left, using the pen to draw a few other symbols in a horizontal line. He couldn’t help but notice the subtle sound of bones rattling as he worked.

_ “Star signs.” _

Sans stared at the paper, then he gave Grillby a pointed look, his grin widening. “say that again?”

The corner of Grillby’s mouth twitched, but he was amused nonetheless. As Grillby wrote a few more symbols down, he played with an idea as Sans watched him. Then the fire monster repeated the two words, this time quieter.

Sans watched him with interest. The way Grillby had revealed it was so mesmerising that a soft “wow” escaped Sans in a bare whisper. He recognised that the numerous symbols Grillby drew were from astronomy textbooks, and others were foreign-looking and looked nothing like the script that Sans was attempting to decipher.

So he looked back to Grillby and up to his face, moving left hand to reach out to him.

Grillby’s fire flickered briefly, the subtle hues of orange and red light shifting into an almost opalescent amber. Enthralled by the change in Grillby’s colouring, Sans twisted so he faced him and carefully rested two digits on either side of the fire monster’s face, one on each frame of his glasses.

_ “What are you planning?” _ Grillby murmured, the corner of his mouth twitching again into a wry smile.

Sans felt himself flush but didn’t move his hands away. Instead, he tipped Grillby’s glasses down, his gaze never straying. The flames’ colours lightened into paler yellows again and Sans saw a wisp or two of white until they quickly rolled away.

“i just want a better view,” the skeleton replied, grinning. He kind of appreciated the way he was able to get Grillby all fired up, when it’d been almost completely one-sided lately. Slowly, he took the glasses away and Grillby noticeably squinted.

_ “…Cannot see you like this, friend.” _

Grillby leaned a little towards him as though to see better and Sans’ soul shuddered with excitement. He felt a peculiar little spike in energy as their faces drew nearer, but Sans somehow kept himself together. So far, Grillby seemed content to let him do whatever he wanted.

“that’s cool,” Sans replied indifferently even as he put the glasses onto the table and brought his hands back to Grillby’s face. It mirrored all the times Grillby had held his own, deliberate with the fire monster’s intentions. As he did so, Grillby’s fire rolled down to Sans’ wrists and heated the joints between his carpals. The warmth had him sighing pleasantly.

He was close enough to see directly into Grillby’s eyes. Sans didn’t know what sprung it, but knew he had to see for himself. Sans had stared all he’d wanted to the night that he’d confessed, but the dark-framed glasses muted the true reflection of Grillby’s gaze. As though bashful, wisps of flame tried to hide Grillby’s expression, but Sans was too close for them to do any good. He knew his staring was having an effect on Grillby and Sans couldn’t help but grin in turn.

With that, Grillby’s flames kindled a little higher, flecked with white embers.  _ “What are-” _

Sans shook his head to interrupt him. He wasn’t sure if it was something Grillby could recognise without his glasses, but the fire monster stopped regardless.

“i just wanna see.”

Sans’ soul started to hammer hard, but he stayed calm for once. Sans couldn’t help the snicker that escaped him when he saw Grillby’s bright irises dart to the side and the heat kick up a little hotter. Heat that Sans hadn’t been able to fully appreciate until recently.

It felt kind of  _ nice _ to be able to do this back, to have the fire monster feel the same as Sans did in the past to get him flustered. While Grillby could still exploit that feeling, Sans was a little proud of how increasingly bold he was becoming the more he thought about it.

He brushed his bony fingers against Grillby’s face and watched as small pinpoints of light and colour filled his fiery eyes. They cascaded around fiery clouds of cobalt, magenta and green, while the small points of light were white, small specks of red and blue like hidden stars. It reminded Sans of when he’d spend hours looking through old textbooks for photos of galaxies when he was younger, or the fiery opals embedded in the cave walls between Waterfall and Hotland.

Grillby flushed again, brighter, small embers drifting around them in different colours of white and blue. Sans couldn’t help but grin more as the bright flames obscured Grillby’s eyes.

_ “I think you’re enjoying this,” _ Grillby finally murmured, his voice quiet and a little shy. There was a bare waver to it that made Sans’ magic thunder loudly within his head. When he dropped his gaze for a split second, Sans noticed that Grillby’s gloved hands had grasped the edge of the table and on the cushion by his leg, as though the fire monster was trying to keep his hands to himself.

Admirable, Sans thought.

“‘course i am. i’m just doin’ a little star-gazing,” he teased, and Sans felt heat rise to his face when he heard the words out loud. He witnessed another bright reaction and couldn’t help but chuckle. Grillby had shrunk down and was even laughing quietly despite himself. “how… how else am i gonna get up close and personal with the universe like this?”

It must’ve been something that Grillby hadn’t expected, since his flames seemed to entirely immolate his face like a small explosion. Instinctively, Sans pulled his hands away, searching for any hint that he should apologise for what he said. Maybe he’d gone too far? A twist flared up inside of him when Grillby covered his face, the pale yellow and white flames thrumming around his head and fingers. Grillby remained quiet, but he was  _ bright. _

Sans leaned back and idly scratched at his jaw. He wasn’t sure if he’d embarrassed Grillby or not, but he had a feeling that he messed  _ something _ up. When Grillby’s fire returned to a softer shade of orange, Grillby appeared to be calmer, though he fumbled for his glasses. Automatically, Sans held them out for him to take, his own magic’s flush apparent on his face.

“sorry,” he muttered with a shrug when Grillby was finally able to look at him. The glasses obscured the view of his opaline gaze and made his eyes look fiery again.

The silence stretched on, and eventually Sans’ figurative nerves finally gave out. He began to fidget and drum his fingertips on the tabletop, picked up his pen and set it down. Then, sparked by an idea, he picked it back up again to scribble in the margin of his notebook.

He figured Grillby must’ve been uncomfortable enough to want to leave, since the fire monster had slid out from beside him once he’d calmed down. Disappointed in himself, Sans turned his head to watch the bartender leave, just as he heard something under Grillby’s breath.

_ “Point for you.” _

Sans only stared in stunned silence as Grillby went back to work. He’d stay away, but he had to smirk when he caught a certain someone watching him. Abashed, it caused Sans to turn his head back to his own project on more than one occasion.

Sans hesitated for the longest time before he resigned himself and sent Alphys a few texts. 

Alphys (Last message received: 7:37pm);

*k so   
*whats it mean when a guy is keepin score   
*n by keepin score i mean hes givin out points   
*is this normally how datin works??

\- One sec! I’ll ask Undyne! Σｄ(ﾟ∀ﾟ)

*o what no   
*no way   
*alph pls   
*dont   
*gdi u already did

In the span of what it took for two excited ladies to gossip about his private life and probably speculate far too much, Sans’ phone rang. The call was from Undyne, so naturally Sans ignored it. A fresh wave of embarrassment poured over him like a torrent, as though he’d decided to stand under a waterfall.

His phone rang again.

Then again.

He received a few texts from Alphys asking why he wasn’t answering and that apparently Undyne had some very good advice for him. Sans decided to ignore those too and covered his face with both hands, rubbing at his eyes with his palms until his phone stopped buzzing. When he eventually checked, he had over 40 messages from Alphys and 12 from Undyne.

And one from Grillby: 3/3.

Sans supposed it was Grillby’s way of keeping score, although he wasn’t sure why it was necessary. He sure as hell knew he didn’t want to be badgered by prying questions, though.

Shyly, Sans shot a grin from across the bar to the fire monster and turned off his phone so he could concentrate without further interruptions. Eventually, Sans ended up laying his head in his arms to take a nap.

  
  


It was a lot quieter when Sans next woke up, but it was to a light  _ thunk _ of knocking on the table. Grillby slipped into the seat across from him as Sans inched up from where he sat, turning his head to regard him. Naturally, Grillby’s flames were back to normal and his expression was neutral.

“papyrus didn’t come by yet, did he?” Sans yawned, his jaw clicking. When he stretched, several of his bones popped audibly.

_ “…Closed. Should not be long now.” _

Sans rubbed at one of his eyes before looking around the bar; it was definitely empty, no one else there and the oil lamps on the walls were turned down so Grillby remained the primary light source.

Knowing that Sans would ask why he wasn’t kicked out, Grillby added;  _ “You seemed… tired, today.” _

“when it’s a day off, i’m allowed to be tired.” Sans rolled his shoulder before he rested his head back down into his arms. “i can’t remember the cipher, so i guess the dimensional box is gonna stay broken for a bit.”

Grillby’s back straightened slightly at that. He looked enquiringly at Sans until his gaze was returned, Sans’ expression exhausted and mostly indifferent.

“what.”

Grillby pulled one of the notebooks towards him. Alongside the many diagrams, there were many more calculations added to it than before and Sans had even included a detailed schematic. It looked extremely convoluted and didn’t make a great deal of sense.

Grillby stayed silent for awhile, until he finally decided on;  _ “…You can repair them?” _

“i make ‘em,” Sans revealed with a vague shrug, closing his eyes. He hoped that it’d be a little longer before Papyrus arrived. He liked chatting with Grillby. “it’s been, uh… quite a few years since the last one, though.”

_ “……Make them?” _ The startling disbelief in Grillby’s tone was enough to pull Sans from another impromptu doze and he cracked open an eye.  _ “You make them?” _

“simmer down, grillbz. it’s no biggie.”

_ “You fail to acknowledge the magnitude of this,” _ Grillby retorted with a scoff, and his flames started to hike up and dance. He spoke quickly and with a hard edge, something that Sans thought a little peculiar.

“you’re getting too excited over something like this.”

_ “They are used all over the Underground, Sans. They are the reason I was able to leave Hotland, I-” _

Sans pushed himself off the tabletop, feeling like it was too much attention all at once. As a result, he began to feel a little sheepish. “oh.” Awkwardly, he scratched the back of his head. “and here pap tells me it’s the laziest thing i’ve done, making everyone reliant on them.”

_ “…Must confront him about this. It is truly a revolutionary and indispensable part of our lives now. However did you think of it?” _

Sans flushed at the excitement and quietly drummed his fingertips on the tabletop. His gaze briefly settled onto his right arm, soberly recalling his recovery time in New Home after his fall at the CORE. Admittedly, the boxes had made it easier for him to move things around back then. It certainly helped with covertly moving around. Sans realised that he’d been frowning and schooled his expression, tightening his grin to look up. “oh… y’know. core stuff.”

Grillby had caught the expression and looked suspicious. He managed to conceal it when Sans glanced back at him.  _ “CORE ‘stuff’? And yet even more infuriating vagueness about past works.” _

“i dunno about infuriating…” Sans shrugged, toeing the line between deserting the conversation by straight up leaving the restaurant or by flipping the subject around. Unfortunately, he knew that Grillby wouldn’t drop it so easily. “nah. i mean, i already said i worked there. this was just a side project while my group was…” He paused and shifted slightly as the little white lie formed unbidden in his mind,  _ “…fixing _ things. it was part of the research i helped develop, so it, uh…” He let the rest of it hang. Suddenly he felt extremely awkward, perhaps by the need to explain himself, or by the way he felt concealing the truth.

Grillby relaxed a little, but Sans could still detect his excitement. His flames flickered and even looped around the surface of his exposed neck, kindling brightly. Absently, Sans scratched the side of his head, unable to meet the fire monster’s gaze for long.

_ “Interesting.” _

Sans flushed at that and floundered for a way to drop the subject. “i mean… it ties in with my shortcuts, so it’s nothing really, uh…”

_ “No need to be modest. It’s very impressive.”  _ Grillby smirked at Sans’ reaction, his expression warm.  _ “Is it something your brother can achieve as well?” _

Evasively, Sans shrugged. “he can’t, no…” But there were  _ other, _ stranger things Papyrus could do, but Sans’ ‘shortcuts’ were his alone. “i’d make a box from scratch, but it takes some materials i can only get from, uh… private resources. that, and all i can remember is that it takes a lot outta me.”

_ “Did something happen?” _

Sans fell silent, but then quietly sighed. “it’s just been awhile. i gotta remember how to stabilise the gridline and affix it to a vessel. but all my notes -- as you can see -- are in cipher, so it’s gonna take a bit. i was thinking that maybe you can help me.”

Grillby’s curiosity was piqued.  _ “…I can?” _

Sans shrugged and spread out his hands to the notes. “you said a few ciphers looked like star signs?” He paused, and after a moment an idea came to mind. “you use hands too.”

_ Except with me, _ he added internally.

Grillby nodded in the affirmative and watched as Sans turned to a page in his notes that had swathes of symbols, drawn in thick black ink. A lot of them appeared to be legible representations of gestures and the pages were stained, old and crisp.

Sans turned the notebook around so Grillby could easily read it and watched as Grillby leaned forward to study each one. Then, as though it suddenly registered, Grillby raised a hand and gestured.

Sans paused every time something clicked into place. It was peculiar, bringing up a confused sense of nostalgia, like he’d forgotten something and it was now up to Sans to bring all the pieces together again. It was also strange, considering that Grillby rarely used gestures to communicate with him. He hadn’t seen them in forever. To his knowledge, Sans was the only person that Grillby took the effort to actually  _ talk  _ to.

It was endearing in its own little way. If he looked a little deeper, Sans would’ve seen it for what it was: Grillby liked talking with Sans to the point where that personal barrier had been broken down, long ago.

They weren’t words as regular hand gestures were. ☼︎ was ‘R’, ✌︎ was ‘A’, and so on, corresponding with every letter of the alphabet. Sans frowned as he focused on them and drew out a glossary for future reference. He recognised quite a few of the gestures, having used them  _ himself _ to access the panel at the CORE. So why didn’t any of them make sense when he viewed them on his own?

Sans sighed to himself and doodled a few of them out. He was tired, but he wanted to try one more thing, one last thing to get a reaction out of Grillby. There was another peculiar spike in his energy when Sans thought about it, how his soul trembled when he recognised just what he was doing. When he finished the sentence in Hands, he flipped and pushed the sheet of paper across the table for Grillby to translate.

He kept his gaze fixed on the fire monster’s face and Sans’ grin twitched shyly when each symbol was flicked by Grillby’s hand. He flushed as realisation dawned in Grillby’s eyes, and Grillby’s hand suddenly stilled at the last motion. Looking pleasantly surprised, Grillby’s gaze settled on him.

_ “‘Go on a date with me’,” _ Grillby recited, his tone warm and rich. He grinned, then laughed good-naturedly at the proposal, which had Sans blushing furiously, embarrassed and shy to hear it out loud. Grillby glowed brightly, delighted, but he waved at Sans to get his attention. When Sans turned to face him again, face beaming, Grillby gestured so precisely that it was unmistakable what his intentions were.

_ ‘Pick a time and place. I would not miss it for the world.’ _

**Notes for the Chapter:**

> I should really type out what I want to say when I finish these chapters, because now I forget. Guess I'll ramble!! See, it's not one-sided. Sans can definitely make Grillby flustered!! 
> 
> blackberryvenom on tumblr drew some AWESOME fan art of Sans and Alphys from this chapter!! [YOU SHOULD CHECK IT OUT!!!!](http://skerbaderbadoo.tumblr.com/post/171760107807/)


	7. Chapter 7

**Summary for the Chapter:**

> Papyrus knows. Undyne knows about the date. It's only a matter of time before the whole Underground knows. Sans decides to study at Grillby's. There is a heated moment during breakfast.

Alphys (Last message sent: 7:06am);

*omg u told her   
*cant believe it   
*the whole ugs gonna know now   
*between undyne n pap   
*omg papyrus   
*what if she told pap   
*alph what have u done

\- Okay so maybe don’t panic!! (￣□￣)

*how   
*u basically went from bff 2 foe in 1 fell swoop

\- You’re being overly dramatic!! ( ￣＾￣)

*no u dont understand pap has been hintin   
*ugh he already knows   
*ugh he just said audible wink he definitely knows   
*fuck

\- Stop freaking out LOL you’re going to be fiiiiiine (´∀｀；)

*omg hes givin me tips bout datin   
*how dare u

\- And by fine I mean take some time off!!! Undyne’s already approved it. ☆=(ゝω･)/   
\- I don’t know why the heck you’re not studying up on the bio textbooks you asked for?   
\- YOU ASKED FOR THEM   
\- READ THEM, SANS!!

*alph u know ur my bff n all but i could literally blast a hole in the barrier rn

\- Trust me, if that’s all it took I would have pissed you off YEARS AGO   
\- Hahaha… Just kidding (ノ﹏ヽ) That wasn’t funny.

*im goin @grillbz pap is bein distractin so ttyl

Undyne (Last message received: 7:43am);

\- YOU!! HEARD THE BIG NEWS YA GOOBER!! Can’t say I’m surprised! You’ve been spacy for WEEKS!   
\- So who’s the flame? Papyrus doesn’t know ANYTHING. I can’t get ANY DETAILS!   
\- IS THIS SOMETHING YOU’VE BEEN HIDING FROM HIM??   
\- Maybe don’t… y’know, do that anymore? Kid worries enough as it is about ya.   
\- PS: In case Alphys hasn’t told you yet you’re TOTALLY FIRED.

*what

\- HAHA gotcha! I’m only joking, of course. You got the next couple of days OFF!   
\- I’M GOING TO QUIZ YOU SO YOU BETTER STUDY HARD LIKE THE HUGE NERD YOU ARE.

He was irritable, aggravated, and a little pissed off. Sans shoved as many textbooks as he could into his bag, ignoring the continuous knocking at his bedroom door. Papyrus’ voice had just reached its ultimate crescendo on dating. A lot of it didn’t make any sense and made Sans so flustered that he just didn’t have the words to tell his brother to shut up any longer.

“i’m leaving!” he hollered over the informative lecturer from beyond the door. Then with a burst of energy that had over-accumulated during the night, Sans simply teleported out of his room and reappeared behind Grillby’s restaurant. It’d certainly be less of a distraction than being at home.

As Sans rounded the corner, he heard his phone buzz in his pocket and weighed the pros and cons of throwing it onto the roof.

He resisted in the end, but a series of vibrations told him that he’d received quite a few texts in quick succession. Wordlessly, Sans pushed the door open and chose a booth nearer to the door, in case he needed to make a quick getaway.

With all his books laid out, Sans started to read  _ E/M FLUX BIOLOGY _ first since it was hundreds of pages long and was bound to have the most information. It also had an informative introduction with an index so Sans could flip through different subjects at his leisure.

Since it was early, Grillby was still setting up. The soft scuffs of chairs on the hardwood floors and the gentle clinks of glasses knocking together filled the quiet air as Sans studied. Generally, Sans didn’t come in until after noon, but his lack of greeting wasn’t abnormal. The fact that he’d taken a seat towards the front of the bar was.

As Grillby moved about the floorspace to set up, Sans shifted to take out his phone, far more irritable than he’d ever felt before. He ignored more messages from Alphys (badgering him about him studying, no doubt) and went to Papyrus’.

Papyrus (Last message received: 8:23am);

\- OH MY GOD!   
\- DID YOU JUST USE THE WINDOW TO ESCAPE?   
\- HOW INCREDIBLY IMMATURE AND… WILY OF YOU, SANS.   
\- BUT NO MATTER, THE GREAT PAPYRUS WILL ‘SCHOOL’ YOU WITH YET MORE BROTHERLY UNDERSTANDING.   
\- WHILE I KNOW YOU HAVE BEEN NEGLECTING PROPER EATING HABITS LATELY, I DON’T BELIEVE YOU ARE GOING HUNGRY.   
\- QUITE THE CONTRARY!! AFTER ALL, YOU HAVE A HOT NEW BOYFRIEND WHO COOKS. OF COURSE YOU WOULD FEEL OBLIGATED TO EAT HIS DISGUSTING GREASE-LADEN FOOD!   
\- WHAT KIND OF BROTHER WOULD I BE TO STAND IN THE WAY OF TRUE LOVE? NOT THE KIND OF BROTHER I AM WELL-KNOWN FOR BEING!   
\- THE GREAT PAPYRUS WILLINGLY ACKNOWLEDGES THIS TURN OF EVENTS. BUT! IF YOU ARE EVER IN NEED OF SOMETHING TO REFRESH YOUR PALATE, THERE WILL ALWAYS BE A DELICIOUS MEAL WAITING FOR YOU AT HOME!   
\- HAVE FUN STUDYING!! 

News got around in his circle of friends fast. Sans groused internally as he glared at the phone and tapped out a response, but then he ended up deleting it. Deeming it with a reply would only invite more messages, so he pocketed the phone and dropped his head against the open tome with an audible  _ thunk. _

_ “…Up early this morning,” _ he heard Grillby’s voice gently call to him from above. Sans moved his head to the side and flicked his eye lights up to regard him. With the quiet hum and crackle of fire, his mood instantly eased a little. Then Sans recognised the peculiar way Grillby examined his books and pushed himself off the table.

“studying.”

_ “Had breakfast?” _

Sans slowly shook his head and blearily rubbed at an eye with the heel of his palm. He didn’t say anything, but Grillby had already left before Sans had a chance to think about what he could order. He wasn’t particularly worried as he’d gone without breakfast many times before, so Sans forced himself to read a little more.

It wasn’t until the fire monster returned with a plate that Sans realised how hungry he was, nearly a full hour later. He supposed that the time taken was simply because Grillby didn’t normally offer breakfast foods. Not that he was expecting anything.

The dish was deep-fried: a waffle of fluffy yet crisp consistency with a thin red peppered sauce in a square ramekin on a plate. Sans couldn’t help but grin down at it in anticipation, almost too good to break apart and ruin the meal by eating it. Then, because he was hungry and apparently still growing, Sans sectioned off a portion of the waffle and dipped it into the sauce.

Suddenly hesitant, Sans paused. “it’s not ketchup, is it?” he muttered. Quietly, Grillby laughed and patted his shoulder empathically. Sans grinned a little more nervously. “this isn’t on the menu either, is it,” he observed shyly.

_ “…Have not recreated it for years. It’s never been on the menu here.” _

Sans shrugged, the niggling feeling squirming around in his soul like lost fish. It wasn’t lost on him that Grillby was going out of his way to present him with dishes that Grillby didn’t normally serve to his other patrons.

Sans took a bite from the piece to taste. It was sticky, sharp, peppery and eventually, an ungodly spice rolled up his tongue. Reflexively, he covered his mouth to mute the soft hiss that he couldn’t repress as he tried to cool off his mouth. If Sans didn’t know any better (and he didn’t, not really), it had the same effect as the curry bun from Alphys’ lab, but it seemed to have a more energetic kick to it.

_ “Hotland speciality,” _ the fire monster chuckled wryly, giving Sans’ shoulder another pat when Sans blinked back a tear from the heat.  _ “How does it find you?” _

Sans repressed a soft cough as his magic absorbed it, burning all the way. It tingled a little, branching throughout his bones and settling as a dense warmth in his chest. Sans couldn’t keep himself from taking another bite though, still grinning even as he blinked back another spice-induced tear.

“think you’re trying to burn my tongue.”

Grillby stayed quiet as he watched, his expression unreadable as though he made a painstakingly great effort to hide it.  _ “…Perhaps.” _ There was a playfulness to his voice that made Sans pause, having resorted to licking his sticky fingers.

Quizzically, he looked to Grillby’s face to search for any hints, but he couldn’t read anything. Suspicious of Grillby’s reply, Sans popped the rest of the piece into his mouth, exhaling hotly as the spicy sauce kicked around his tongue. It was  _ almost _ too much. The stickiness made it a little sweet after awhile, which he could appreciate, and the heat in his mouth was manageable after the initial burn.

Since Grillby hadn’t said anything further, Sans turned the page of the open book with his other hand while his tongue curled against his index finger, lapping up the sticky mess the sauce had made.

It occurred to Sans a little belatedly that maybe he should’ve used a fork. That is, he  _ would’ve _ if Grillby hadn’t taken his left hand, catching his attention. Sans’ gaze flicked to the fire monster’s face, still obscured, but he could see the glowing crack of his smile. Sans grinned despite himself, apologetic as well as a little shy thanks to how close Grillby was.

“sorry, i’ll use a napk-”

He was cut off as the fire monster slowly drew closer, resounding an audible  _ thump _ in his rib cage when Grillby leaned in with his body. Sans froze, staring, his mind coming to a screeching halt when Grillby’s mouth touched his own. His soul shuddered with it as flames danced over his teeth, automatically parting ever so slightly to drink in the heat that Sans had felt the night he’d confessed. Grillby’s touch had him reeling as he sank down beside Sans, his hold on his hand gentling.

Sans sighed against the kiss and carefully pushed a bare inch forward as he closed his eyes. He felt the unmistakable warmth and something like heady spices trace against the part of his mouth, gentle with its coaxing invite. Sans shuddered and experimentally pushed his tongue forward to meet with it, wondering how it’d taste in comparison to the sauce.

The intense heat sent a pulse throughout him when their tongues touched, a gentle hiss between them when wetness met heat. A surprised jolt settled down Sans’ spine when Grillby’s hand braced against his back, spreading a dense molten throb to pinpoint his touch. For a moment, Sans thought that he saw a brief flash of light behind his eyes when the spread of flames fluttered around him.

A noise escaped Sans before he even realised what was happening. His thoughts melted, forgetting how to breathe or to move, stuck only on the thought that it felt  _ amazing. _ His moan punctuated just how much Sans was enjoying himself as he attempted to lean forward, hesitant. Heat and spice entered his mouth and mingled with his tongue, soft and slow like melted sugar.

Sans settled his right hand between them, not really knowing what else to do with it. But he  _ definitely _ knew that he wanted more of this.

He kissed back, his soul feeling like it was doing small flips as he attempted to mimic the way Grillby’s tongue plied him. The slow curling movements left him aching and the soft small circles had his toes rising in his slippers. Grillby’s hand found the back of his neck as he led Sans, the flood of fire both soothing and passionate. His fingers interlaced Sans’ and Grillby lightly tugged him forward with a soft hum. Sans instantly melted into it, accepting everything that Grillby offered, the heat of his magic searing his face. His magic surged, curling with an intense need to touch when Grillby pulled away much too soon for his liking.

It’d left Sans breathless and gasping, even for a monster that didn’t really need air. Unable to help himself, he panted and leaned his skull against Grillby’s forehead, unable to hold back the soft noise of protest that passed between them. Grillby was of a similar composure but he grinned and traced a line of heat against the bones of Sans’ neck and around to his jaw with the pad of his finger.

_ “Been wanting to do that… for some time.” _

Sans huffed, unable to contain a quiet laugh. If there’d been any doubt that their friendship had somehow changed, it was long gone now.

“…spicy,” he murmured, still half-stunned as he looked at Grillby. Sans had the urge to continue and felt his face flush at the thought. Whether or not that was due to Grillby’s heat, well… he had no complaints. Bolder now, he twisted his body so that he was more comfortable. Then Sans inched his right arm up and around Grillby’s shoulder to pull himself closer. “wanna do that again..?”

With the quirk of Grillby’s grin and a flicker of his flames, Sans dipped his face a little so their mouths were barely apart. He wanted to try putting his tongue on the fire to see what would happen, but the thought was extinguished when Grillby chuckled softly and regretfully pulled away. Sans felt the loss immediately, though his interest in Grillby’s paler flames grew.

_ “We have a guest.” _

For the first time in awhile, Sans felt as though his soul was about to drop out of his rib cage and he became deathly silent. Cautiously, he peered over Grillby’s shoulder to see Doggo surveying a restaurant that likely appeared empty but left open. Sans breathed a quiet sigh of relief and slowly sat back as to not rouse an alarm. Grillby then took it upon himself to bring Sans’ left hand up to his mouth to leave a kiss, and sent him a knowing wink.

Sans attempted not to scowl at the intruder when Grillby moved away from him, feeling more than a little spurned for the interruption, though he didn’t want to address that too much. He felt more irritated than when he’d left the house, and Sans impatiently waited while the fire monster addressed Doggo with a series of lively gestures.

An order to go. Sans couldn’t help but feel a little bitter with the relief that came with the knowledge. While there wasn’t exactly any animosity between him and Doggo, Sans had earlier discovered a bet made by the dog and a couple of others, and with  _ this, _ it made him a little peeved.

When Grillby went back to the kitchen, Sans conjured a small length of bone and whistled lowly, beckoning the unwelcome guest’s attention. Doggo’s ears cocked at the noise and Sans grinned impishly.

“think fast,” he called out, and flicked the bone towards Doggo’s muzzle with his magic. It would’ve connected had he not said anything, but it was also moving. Doggo caught it after looking into Sans’ direction, his eyes scanning suspiciously. His fangs sunk into the bone with a veiled snarl and Sans sunk back onto the bench, keeping still as he read over the next page.

The glow of his magic was more of an aggravated flicker now and he desperately tried to hold it at bay when the bartender came back into view. Sans watched out of the corner of his eye when Doggo finally left and made a mental note to pull a prank or two on the guard dog later on.

His magic flickered a little more. It felt like an itch that needed to be scratched and Sans absently rubbed at his sternum as he read, trying to keep calm. He spent hours poured over the textbook and Grillby offered him a drink a time or two, but Sans quietly declined. It was as though Doggo’s interruption had soured his entire mood.

After awhile, he took a break. People started to trickle in as the day progressed and Sans was ready to blow off some excess energy. Alphys had warned him against doing so, and ultimately the textbook informed him of the reason why.

In chapter 14: ‘Magical Fluctuations & Aggression’, he found it; marked with skirmishes, spikes in energy flow and increased irritability, Sans was a textbook example and he hated it. He tapped his fingers against the page as his gaze wandered over the restaurant, his eye lights dimmed until they found Grillby at the opposite side of the bar, watching him.

Sans flushed; which was another thing that marked development, but it was usually unique to certain species. Chapter 18 dealt with the more literal ways to contend with rising magic levels in relation to HP values. Sans glared at the acronym and shifted his hoodie so it covered the sides of his face, suddenly wanting to hide from the world.

There was another passage that pretty much told Sans that he was screwed; that parents could calm an adolescent’s magic if they were irritated or out of control. He realised that he’d felt a little bitter about it lately, as though having a parent around would make this all a little easier to handle. It was the reason why he felt so tired but had so much pent-up energy.

When he thought about it, Sans vaguely remembered a few puzzles that Papyrus had come up with during his days experimenting with magic. Sans recalled that it’d been the only time when his brother had actually slept more than a few hours each night. He’d have to speak with him about it later. He really wasn’t looking forward to it.

Reading the textbook bewildered Sans. There was so much information that he’d passed on just because his body was in permanent stasis, and he’d been given a great excuse to ignore it. But as for Papyrus, Sans felt a little ashamed and even angry at himself. He should’ve known all of this for  _ Papyrus’ _ sake; he’d been horribly negligent. As the older brother, Sans felt that he should’ve at least tried a little better. He should have been the one to teach him about these kinds of things…

Sans mentally berated himself for it as he continued to read. At least there had been a saving grace with Papyrus’ unquenchable thirst for knowledge; the kid pestered every adult he could find for the information he needed. He idly wondered if Papyrus found out any relevant information from Old Gerson about skeletons before his memory got too bad.

There were three chapters that had him briefly skimming the topic, covering attraction and mating rituals by different monster cultures. Sans could feel the heat of his face and his soul thunder inside of him, nervous as though other people would find out what he was reading by just looking at him. He took frequent glances to Grillby, who was kept busy by his customers and never appeared to be looking when Sans chose to spy on him.

It occurred to Sans that he hadn’t chosen a day or place for their first date. He grabbed the front of his hoodie as his magic pulsed again, trying not to attract too much attention and cursing the damned lightshow. It was a good thing he was out of direct sight. If he’d been at his usual seat or by the back of the bar, others would no doubt try to talk to him about it. Or worse,  _ tease him. _

He turned a page. Something was stuck to it on the back, something old, creased and severely water-damaged. It took a moment for Sans to recognise what he was looking at before his eyes widened in shock.

It was… a skeleton. Not like him, nor was it like Papyrus. It wasn’t anyone he would’ve known but he quickly decided that they  _ couldn’t _ be. They were drawn in thin lines with lettered print so ruined it was impossible to make out. Sans squinted at the page, confusion overcoming him as he traced over the image with his fingertip, eyeing the flecks of red and faded orange stuck to their bones.

They really did look like some kind of skeleton, but the drawing was too old to really tell. Sans stared at the page for what seemed like an eternity. Femur, radius, skull, pelvis and ribs… a strong spine, resembling his brother’s, but oddly different. The swatches of faded colour made it look kind of lumpy, which only added to Sans’ confusion.

“the hell is this…” he muttered quietly to himself.

Carefully, Sans peeled the paper stuck to the page and turned it over. There were more diagrams that showed metacarpals and phalanges upon its reveal, seemingly labelled and coloured to show the different bone segments, but the print was still illegible. Sans compared his own hand to that on the back of the loose page, his brow bone furrowed in thought. For a moment, he wondered how old the skeleton drawing was. It had to be older than  _ he _ was at the very least, as Sans had never seen another skeleton monster apart from Papyrus.

Something twinged in his head. He flinched, the rush of static amping up like a shock and Sans put his hand to his temple to soothe the ache. He’d tried to think of what his parents were like, but grasping for missing memories caused him pain lately. It was as though it was a punishment, almost.

If anything, it was probably just an artist’s rendition of a monster. Sans wondered why Alphys would’ve included it in the textbook and quickly shot off a few messages to demand why. She answered back soon enough, only mentioning that she had found it earlier that year during one of her searches through the dump. She thought it would’ve helped him. She also apologised like she always did, even though it wasn’t necessary.

That explained it, then. It wasn’t helpful, as it was just a naked skeleton with what looked like either meaty bits or clothes, possibly ecto-parts. The page didn’t have any information that Sans  _ needed, _ and Gerson had very limited knowledge that he could recall.

Defeated, Sans sighed and texted her back his thanks anyway.

For a while, Sans only had tunnel vision for the drawing. It was weird. They were  _ naked.  _ Something about their eye sockets looked distressed, and a cursory glance told Sans that neither he nor Papyrus were like them at all. They were drawn so stiff-looking that Sans wondered if the reference had been someone who was on the verge of Falling Down, and that it possibly was meant as some kind of memorial.

It was just so unearthly and  _ creepy. _ And for that matter, there was no representation of the soul, opposed to other monster illustrations that Sans had seen in the past.

They were just… empty.

It came to him rather slowly. It wasn’t a person. Chances are that it’d never been a person. It was a  _ thing. _

It took him several moments of pensive silence until Sans noticed that Grillby had snuck up to his booth. Sans flicked his eye lights forward and up, realising that the fire monster seemed very interested in his reading material. He also appeared to be waiting for an answer. Sans hadn’t even registered being asked a question as he stared down the weird skeleton-like monster…  _ thing _ .

Apologetically, Sans grinned and set the page down, shrugging in the way he always did when he didn’t catch whatever the fire monster said.

It took Grillby a moment longer to repeat himself, shifting in place as he inclined his head. He seemed a little brighter than that morning, Sans noted with mild interest.

_ “…Working hard?” _ Grillby attempted, and for some reason Sans felt like that hadn’t been his initial question.

“sure. learning some stuff that’s not really in my field.” Sans leaned back against the booth and sighed as he arched his spine, not realising how tense he’d become. “it’s kinda out of my element.”

_ “…And what is?” _ Grillby inquired. Something about him seemed distracted.  _ “Your element?” _

Sans regarded him for a moment, not sure if he should be literal and say ‘physics’ or not. Then he grinned, leaning forward.

“calcium.” Pretty clever, he thought. 

Grillby repeated the word as though he didn’t fully understand if there was a joke there, but then he went quiet.

“i’d put it on the  _ table _ but it’s not something i fire up  _ periodically.” _ Sans sniggered to himself; it was a bad joke. The worse they were, the better the reaction.

Grillby remained in silence awhile longer, as though savouring every moment Sans grinned cheekily up at him. Then he finally exhaled a small plume of steam and rubbed a hand over the flames at his neck.

_ “That was a stretch.” _

“i’m feeling kinda burnt out.” It was true, but the joke also had a double meaning thanks to the kiss. Sans winked at Grillby, who only shook his head in response. “what’s up, grillbz?”

Sans looked around, feeling idly shy all of a sudden. The bar was still full of customers and realisation dawned upon Sans that the fire monster often took breaks when he was around. And others watched, curious. He flushed a little, reigning in his magic so the flicker under his hoodie was subdued.

_ “…Seem agitated.” _

“me?” Sans scratched the side of his skull and looked down to the textbook. He couldn’t keep from idly drumming his fingertips on the table in thought.

_ “Perhaps I was too forward this morning.” _

Sans detected a trace of regret in Grillby’s tone and quickly glanced up. His flames were a little lower and he wasn’t looking at him, but his gaze remained transfixed on Sans’ reading material.

Sans thought back to the toe-curling kiss and leaned forward, unable to keep himself from grinning. “nah.” In fact, now that the fire monster had time to visit, he wanted another. But… there were people around, and suddenly Sans felt very conscious of the fact that every eye was watching them. And those who didn’t have eyes were keeping tabs, too.

Grillby nodded, but it looked like it was more to himself than to what Sans said. Carefully, he leaned against the table, picking up the old page to examine it. Unsure why, Sans felt his magic pulse at the peculiar way the fire monster expressed interest in it.

_ “Your magic…” _ Grillby started, quietly. Sans saw how Grillby’s gaze moved and settled on him before he dropped his own to his hoodie. Sans grabbed the fabric in his fist, trying to subdue another annoyingly bright flicker.  _ “…It resembled lightning, just now.” _

“it’s just a, uh… skeleton thing,” Sans excused it, chancing another glance to Grillby’s face. “no need to grill me on it.”

At least that had earned him a small smile. Sans sighed quietly with relief; for a moment, he thought something had gone wrong without even realising that he was feeling it in the first place.

_ “Why are you studying such… provocative material at my restaurant, Sans..?” _

It was the longest three seconds that Sans had ever suffered through. There was another spike of energy as he darted his hand out to grab the page from Grillby’s grasp, nearly tearing it in the process. Sans realised what that must’ve looked like only  _ after _ the fire monster had taken a rather studious glance over the table, then at the page.

Sans covered his face with both hands after cramming the loose diagram of the not-skeleton into a different textbook, his face feeling hot despite not having any flames touch it.

“re.. research,” was all he could offer as an excuse. His reaction had been more than incriminating, though.

He only heard a soft hum from Grillby, but Sans knew the tone immediately; it was playful and amused, and Sans knew that he’d only given Grillby ammunition for his next attack. He tensed when the fire monster leaned in closer, and Sans could hear every flutter of flame as his soul shuddered traitorously in response. He lowered his hands to the tabletop, trying not to seem too affected.

_ “…Could instruct you,” _ Grillby breathed below the hum of his fire. His mouth was a line of light, curved into a teasing smile as Grillby inched his fingers over to touch Sans’ hand. Sans didn’t know why, but he flinched at the reaction and his soul did an excited little flip.  _ “Why look at a stranger’s anatomy when yours is bound to be much more interesting..?” _

Sans remained frozen in place, but those final words made a subtle shiver of anticipation creep down his shoulders and sink into his spine. His face honestly couldn’t feel any hotter, even if he dunked his skull into the lava in Hotland. He contemplated dunking his head into a snowbank instead, if he could escape.

It certainly was an interesting proposal, if Grillby was serious. Something akin to shell-shock settled over Sans as the thought invaded his mind, of the section he’d skimmed over and its related subjects… And what that would mean, if Grillby had an interest in  _ touching _ him, his hot hands roaming over his bones as he kissed him. Sans’ mind fuzzed into a muted sound of overwhelmed silence, effectively blanking whatever thoughts that sprung up.

He attempted to stammer something out, but the barely-formed sentences dropped like flies. Jokes failed Sans when he tried to be clever, to dispel his flustered state. Grillby only grinned at him teasingly and gently patted the side of his skull as if to say ‘there, there’, but he lingered. His touch was almost like a brand, but it had nothing to do with his ambient heat.

_ “You know…” _ Grillby paused as though in consideration and withdrew his hand from Sans’, then traced a warm line over his jaw. Sans stared agog at him, unable to stop from staring.  _ “…Cannot decide if this counts as one point for me, or two.” _

Sans closed his mouth and opened it again as though to respond, but he couldn’t make a single sound.

Triumphantly, Grillby smirked.  _ “Two it is, then.” _

After that, it was harder to concentrate. Even if the patrons didn’t know what had transpired between the two new lovebirds, Sans’ reactions were proving to be priceless. He flung up his hood during the rest of his studies, keeping his replies brief whenever others passed him by on their way out. Much to his embarrassment, Sans would occasionally see others still watching him when he peeked across the bar to see where Grillby was.

The next time Grillby looked over to his booth, the books remained but Sans was absent. He couldn’t help but grin in silent victory.

It seemed that Sans’ break was enough to calm him down. He re-entered through the door as he’d done on his way out, instead of just showing up in his seat. He’d spent the better part of the past couple of hours agonising over intrusive thoughts and trying to blast a hole into the side of the mountain at his usual spot. On the way back, he’d pranked Doggo a few times as a harmless little payback for the earlier interruption. Sans felt a little fried, but at least the irritation had simmered down and he felt composed enough to answer a few text messages from Undyne in the meantime.

Her messages skipped from topic to topic in quick succession, but the one that he was interested in particular was Grillby’s score keeping. Since Undyne was a monster that lived in Waterfall, Sans wasn’t sure why  _ she _ would know as opposed to Alphys. She figured it was a competition of sorts and told Sans he  _ had _ to win at all costs. He couldn’t help but scowl at that and scrolled through the fire monster’s score updates.

They were up to 5/3, with Grillby in the lead.

Was it a game? Sans wasn’t quite sure if the points he’d earned were given out of merit or not. But then he looked back to the previous evening when he’d gone ‘star-gazing’ and grinned to himself.

Ok, then. He had a plan. He’ll try some tactics to see what it was all about.

He walked to the bar where the fire monster stood by, listening to Red Bird talk about his day. Grillby paused as Sans took his usual spot, though Red continued his story without missing a beat. Sans just grinned and swivelled on the stool.

“hey, grillbz,” he said lowly. He had Grillby’s full attention, but the fire monster didn’t speak. “i got one for you.” Grillby regarded him with something of suspicion in his gaze and his fire wisped languidly as he patiently waited. “you must be the north star, since your light guided me here.”

Sans watched as the fires kindled briefly when Grillby smirked, but he said nothing. Ok, maybe it hadn’t been his best, but Red had at least stopped talking to watch the free entertainment.

“how about this, then? two stars walk into a bar-” Grillby already covered his face, hiding a smile as though he just knew what was coming. Knowing the fire monster’s weakness, Sans couldn’t help but grin as he continued, “one star bragged that they’re the brightest in the sky. the other asked, ‘are you sirius?’”

Red didn’t seem to get it, but it earned a chuckle from Grillby. Sans took that as encouragement to tell a few more jokes and plenty bad -- but that was the whole point. It was his way of testing the waters, as they were, and the more he joked around, the easier Sans felt about it. After a while, Red finally grew disinterested enough to turn and have a deep, meaningful conversation about fishing with the person next to him.

Sans struggled with it for a moment, resorting to mumbling once Grillby drew nearer. “the rumble rows in hotland. this, uh, saturday… afternoon ok?”  _ For a date, _ he wanted to add, but he wasn’t sure if Red was still listening or not.

Grillby appeared to understand what he meant, if the glowing smile was anything to go by. Sans shyly grinned, his confidence bolstered when Grillby nodded in silent agreement just to make sure.

Ultimately, Sans decided to barrell forward and end that topic before he got too embarrassed and stopped talking altogether -- besides, he still had more jokes to tell. Grillby was the sort to take advantage if Sans seemed too flustered, after all. He always made it a little worse, and Sans’ soul always did that funny lurch when Grillby took the opportunity to tease.

“ok. so i gotta ask,” Sans said finally, still chuckling after another pun. Something about planets, posteriors and a certain gas giant. The fire monster’s mouth quirked in a slight smirk, watching him quietly as he paused to wipe down the counter. “did you add extra spices to the food today? ‘cause you’re makin’ my heart burn!”

All in all,  _ that  _ did something; Grillby’s flames paled and throttled against his face, catching everyone’s attention. Sans stopped mid-swivel and marvelled at the sight, his eyes wide. Grillby had stilled as a few snappy embers flew around him, glowing amber. Sans made a soft noise of appreciation, his brow bone lofting in a suggestive way.

“that was bright,” Sans commented, leaning against the counter with renewed bravado. “you must be from heaven, ‘cause you’re outta this world-”

_ “Actually, Orion.” _ It was the first time Grillby dared to speak since Sans had come back from his break.

Sans tilted his stool, mindful of its sway. “so you’re not  _ sirius,” _ he teased, leaning over the counter top. Grillby’s flames eventually returned to their regular shades during his silence. Sans knew that he’d used something like that before and felt a little awkward for repeating the joke. Such a rookie mistake. “uh, gimme a break. i’m winging these. i’m not used to interstellar flight.”

Grillby set aside the cloth he was using to wipe the counter down with and leaned forward so that their conversation wouldn’t be overheard.  _ “Perhaps I could… assist you with the piloting,” _ he replied quietly, a hint of playfulness coming back to his tone. After all, Sans had carried their conversation for the better half of the afternoon.

Sans grinned in response and folded his arms over each other, slouching. “are you saying i don’t know the controls?” He couldn’t help but feel a little awkward at Grillby’s offer, drawing the parallel between Grillby offering to teach him… well, maybe he shouldn’t be thinking about that just yet.

_ “…Handle the joystick?” _

Sans flushed, although he remained ignorant on why. “throttle the engine,” he shot back with a wink and a little too much enthusiasm.

The resulting reaction was captivating, although he couldn’t really understand why, unless it was a euphemism for something else. Grillby hesitated and raised his hands to cover his face, his flames flickering white before they rolled away into yellow and amber. Eventually, his colouring went back to normal but he kept his hand on his face, the temperature much hotter than before.

Sans couldn’t help the hot feeling that flooded throughout his bones. He was trying to stay bold, but Grillby’s reaction made him almost wilt.

During the pause, Sans realised they had an audience again. Eyes were on them, hushed murmurs and giggles marking their little flirtatious display. Sans’ face coloured a little more and he ducked down, none-too-discreetly attempting to hide his flushed expression from view.

“…tie?” he offered, unsure.

_ “Tie,” _ the bartender agreed quietly.

**Notes for the Chapter:**

> They're tied: 5/5.
> 
> The way Grillby speaks is a bit literal, although he tends to drop the subject sometimes, hence the '...' sometimes at the beginning. If you imagine him with a soft British accent, you can see how it works out. :'D
> 
> If anyone would like to view the page Sans is looking at, it's a mix of both the leftmost and 2nd drawings on [this page.](https://www.123rf.com/photo_27151972_old-vintage-anatomy-charts-of-the-human-body-showing-the-skeletal-system-and-various-muscles-four-fi.html)
> 
> Thank you again [Nanenna](https://archiveofourown.org/users/Nanenna) who gave me some awesome one-liners, mainly Grillby's innuendo about studying Sans' anatomy & Papyrus' obligatory jab of "you have a hot new bf so you have to eat his gross food". ♥
> 
> Also: **I've changed the rating from T to M**. Since this chapter is a little dicey, and the next one is questionable (k well not really but it's ~steamy~), I'll stick with the M rating. I am undecided if it'll become E but knowing how I write it probably will at some point. XD;;
> 
> [HolloweenTwinkie](http://holloweentwinkie.tumblr.com/) on tumblr did art of Grillby's HQ flirt and it's greaaaaat aaaaaaa!!!! [Click here to see!!](http://skerbaderbadoo.tumblr.com/post/178080518882) (SFW)


	8. Chapter 8

**Summary for the Chapter:**

> [ DATING START !! ]

_ ‘WE HAVE NOT FINISHED OUR CONVERSATION’ _

If Sans was made awkward and unsure by the looming date that afternoon, it was additionally made worse when he managed to decode the cipher on the back of the old postcard -- the same one that he had received nearly a week prior. Apprehension had built up, discomfort and obscurity mingling with his excitement. The words were familiar again and the cipher made sense now. All of it.

On top of everything else, Sans had made yet another mistake and was subject to the aftermath. He stood awkwardly in his sneakers, a ribbed cream turtleneck pullover and dark red trousers. They’d all been unearthed from the depths of his brother’s wardrobe. It had been after a drawn-out argument and was his final resort after Papyrus insisted on ‘secret clothes’. All of his brother’s clothes chosen for dating were a little more ridiculous, but not by much.

He would’ve worn the trousers without a fight, but Sans just felt  _ naked _ without his hoodie. He couldn’t help but feel a little bitter that Papyrus had added injury to this whole thing by both stealing and hiding it from him.

Apart from the slip up that he had a date, Sans hadn’t been able to get a word in edgewise when his brother took over his preparations that Saturday afternoon.

And this was the result.

At least Papyrus had the sense to modify the trousers to fit him -- plus they had pockets. Sans couldn’t argue with that, since he needed a place to hide each hand, firmly thrusted into the pockets. He had also taken care to bring some money and a small snack, along with this cell phone.

As it had every morning thus far, Sans’ magic had spiked again. Papyrus instructed him to do something ‘constructive’ with it. In lieu of a sparring match, Sans was subjected to intricate little puzzles that gradually filtered away the overflow, but not by much.

He also learned that it was a far better way to outlet, as burning through everything at once was not only dangerous, but could be damaging and lead to bad habits. Sans didn’t like it and he preferred to get it all over with so he could be on his way. He had enough bad habits; what was the harm of adding one more to the pile?

In the snow near the ferry stop just north of town, Sans shuffled as he waited for Grillby to arrive. He was agitated --  _ god, _ he was nervous. The looks he received when he’d left home and went down the street did not go unnoticed. He was glad Papyrus had something other than his own personal ‘secret clothes’, but this somehow seemed like overkill. Somehow, Sans thought he preferred the baseball pauldrons, to be honest.

Sans didn’t feel comfortable. He stuck out like a sore thumb. They weren’t his clothes and he had no idea what Grillby was wearing, or if he would be dressing up either.

Should he have dressed up? It was the Rumble Rows, a racetrack arena. It wasn’t exactly the  _ classiest _ of places to go on a first date, but then again, Sans wasn’t sure how he’d feel in a fancy restaurant or a gala, or anywhere else where he figured a classy guy like Grillby would like to go. Idly, he wondered if Grillby would even have a good time with his decision.

God, he hoped so.

Was it an appropriate place for a date? Was it a little… too much? Maybe they should’ve just gone for a walk through the forest, watched TV, or literally anything else.

It all suddenly seemed like too much, and Sans was drawing close to a panic.

His face flushed at that and he covered it with his hand, turning his back on the path that led from Snowdin. He felt so incredibly awkward and embarrassed. Papyrus knew this and had been teasing him -- ‘boyfriend’ this, and ‘boyfriend’ that. He had learned from Undyne, who had learned from Alphys. Briefly, Sans entertained the thought of outing those two, but they were a different story altogether. They’d get together eventually. Someone else would bring them together, maybe.

Sans heard the crunch of snow and inhaled sharply, freezing in place. He scratched the back of his skull and slowly turned when he heard the unmistakable fiery aura of his date. His soul thundered continuously in his chest, doing that peculiar little flicker that the textbooks had no information on so far. At least the turtleneck hid the majority of the light, Sans groused internally. He’d have to deal with the little cyan beacon that peeked over his collar in the meantime.

Grillby was dressed casually yet snappy, but instead of the vest, his sharp-looking jacket took its place. A dark crimson chemise replaced his usual white button down one, and he wore a matching black tie that was clipped to a row of gold-tone buttons.

Admittedly, Sans felt a little better for dressing up. As uncomfortable as he was, Sans reasoned that he would’ve been even  _ more _ awkward if he had to quickly dash home to change.

The river person had already been paid in advance and was waiting for their little exchange to finish. Sans plucked the collar of his sweater and nodded towards the ferry, unable to speak for fear of saying something stupid. He couldn’t stop staring.

_ “Looking sharp,” _ the fire monster complimented him and stepped up beside Sans. A tremor went through Sans and he concentrated instead on crossing the small gap between the ferry and the bank.

The silence made Grillby smirk, but there was an air of nervousness to him as well. Whether or not it was due to either the date or the river, Sans couldn’t say for sure. Courteously, once the skeleton had mounted the craft, he held out his hand for Grillby to take and offered him a shy grin in return.

Sans noted the lack of gloves with mild surprise, but he didn’t point out the peculiarity.

Grillby huddled on the bench near the exact centre of the vessel and Sans sat next to him. Soon after, they were on their way. The river person whistled lowly as the ferry picked up speed towards Waterfall, singing a little tune with various lyrics that were both whimsical and nonsensical at the same time.

Since his pockets were too high for him to comfortably sit with his hands inside, Sans sat hunched with his hands resting on either side of him on the bench. He concentrated very hard on not allowing himself to worry over every little thing, and glanced at Grillby frequently as though it’d help to show his support.

Grillby’s flames lowered as the craft carried them into the marsh, the distant glow of mushroom gnats and their larvae on the far ceiling sending the telltale blue glow around them. It contrasted beautifully, blues and greens to mix with the ambers and golds of Sans’ companion.

_ “Nervous?” _ It seemed more like a statement than a question and Sans turned to face Grillby, his stiff grin a dead giveaway.

Steam began to rise from the fluttering blaze next to him and Sans felt Grillby’s hand brush against his. Looking down, the fire monster had just barely grazed his pinky against his own, sending a gentle waft of warmth up Sans’ left arm.

“kinda,” Sans fibbed quietly, nudging his pinky towards Grillby in return. It was silly how such a small movement shot excitement throughout him. He couldn’t help but laugh against the rush of water around them as the ferry whisked through to the next stop.

Thankfully, no one boarded at the Waterfall stop and their privacy continued. For a moment, Sans thought he could see a blur and a red glow embedded in the wall as the craft started again.

_ ‘Tra la la~ Beware of the man who came from the other world.’ _

Sans snapped his gaze to the hooded figure in front of them warily. His brow creased slightly, thinking the comment strange, even from the river person -- who was commonly known to be strange in the first place. For once, he decided not to overthink it and gave Grillby’s inquiring look a slight smile.

_ ‘Tre le le~ The water is very wet today.’ _

Sans noticed the subtle flutter of flames next to him become a little more anxious. Encouragingly, he nudged Grillby’s shoulder with his arm and smiled when Grillby turned his attention back to him.

“i think we’re about halfway there,” Sans reported after taking a moment to look around. The heat that rolled off of Grillby’s body had started to create a familiar dense fog. “maybe next time… we’ll just take a quicker route.”

The fire monster seemed to scowl at him, though he took pains to hide it. Sans recalled that Grillby had been upset over his shortcuts -- that, and the mess he’d landed them both in. At least, Sans figured, he only meant with a carry-on, which was likely less than rarely.

Considering he had a buffer, Sans assumed that he’d be fine, but he gave a slight dismissive shrug. It was probably more like Grillby felt uncomfortable travelling such a distance in such a short amount of time, Sans reasoned.

“suit yourself.” He inched his pinky a little closer though, to show his support. He could tell Grillby relaxed at that, if only by a little bit.

While it was a fair distance away, it didn’t take long to reach Hotland. Gratefully, Grillby left the craft first, anxious to get away from the canal. As he stepped out into the dry heat, his fire seemed to crackle and evenly spread out as he waited for Sans to come ashore, embers igniting in its more natural environment. The constant movement made him look well-groomed and filled out. For a moment, Sans appreciated the sight. He whistled lowly before he realised that he was staring again.

He dropped his gaze just as Grillby grinned. It was different dating a friend. They already knew each other, and yet they were still learning things. For one, Grillby noticed that since the shift in their dynamics, Sans was easy to get worked up and flustered. And for Sans, Grillby was a little more interesting and flirtatious. It wasn’t mutually exclusive, but it was endearing all the same. Sans couldn’t help but smirk to himself with that thought.

The walk to the Rumble Rows was a little out of the way but worth it. The arena lay hidden away in an expansive quarry past the elevators and deep into the pits where the city was. Fire elementals, rock-types, some ghosts and their ilk clogged the streets. The stadium was loud and could be heard clear across the lake of lava separating it from the CORE.

Once paid for and inside, the skeleton shrugged, not really having planned all that much ahead of time. He settled for a joke as an excuse, trying to shake off his nerves.

“guess i kinda just wanted to see you all gussied up.” His voice was low enough for Grillby to hear, but no one else. The arena was so packed and the announcer blared a never-ceasing roll of play-by-plays overhead for whichever race was going on further inside.

Grillby rolled his shoulder and took control over their date at that point. While he considered himself shy, it was by Hotland’s standards. Most others would be forward even amongst strangers, whereas he preferred areas where he could be alone with the one he liked most. His restaurant admittedly didn’t count, as it was his home. He wrapped an arm around Sans’ shoulders and led them further inside towards the bleachers.

_ “Shy guy,” _ Grillby teased despite himself. He couldn’t hear the sound of bones clattering together, but the fire monster could certainly feel them. Sans looked extremely nervous, almost petrified.  _ “Play it cool?” _

Sans couldn’t help but laugh at that, twining his sleeve with the tips of his fingers. “i’ve honestly never done this before.” Grillby saved this interesting piece of information for later consideration.

They both went up the stairs onto the metal platforms, pushing past other monsters who didn’t care about the couple from out of town. Sans was flustered, as Grillby had moved his arm from around his shoulders and taken him by the hand. His fire looked as though it was trying to sneak up Sans’ arm from under his long sleeves.

_ “…Should just continue counting up to twenty and beyond. I will get all the points anyway.” _

Sans hoped that was a joke. It didn’t really feel all too serious and Grillby’s composure in such a place made his expressions difficult to see through the blaze. His nervousness did dissipate somewhat when they found a secluded little area towards the middle top rows. It was a great view to the arena below, not that either of them would watch much of what was going on.

“and what happens when i get more points than you?”

Grillby sat, gently pulling the skeleton down with him. He nearly landed on Grillby’s thigh and Sans made sure to scoot over, lest his magic boil over in total mortification of overstepping any boundaries. That was probably a weird thing to think, considering what they’d done at the bar earlier that week.

Grillby seemed to take the question seriously.  _ “Perhaps… fill you with fire.” _

The heat around them made the air hazy and move, pushed by so many fire monsters in one place. Sans belatedly realised that he was perspiring a little and absently wiped the side of his face -- another peculiarity for skeletons, he noted. 

“and what if  _ you  _ win?”

Grillby’s composure seemed to stiffen slightly, then there was a lull in his flames as though something passed through his mind. Curiously, the skeleton stared at him.

_ “What would you say,” _ Grillby started, his voice smooth,  _ “if I won, and wanted that anyway?” _

“that you were blowing a lot of hot air, prob’ly.”

_ “And… what would you do?” _

“if you did..? burn.”

The fire monster hunched slightly as though he was unsatisfied with the answer, but he didn’t make it immediately apparent. Sans avoided his gaze now, his grin sheepish. When Grillby looked to Sans’ hands, they were shaking slightly, clasped over themselves in a near death grip.

As though something had just occurred to him, the fire monster leaned forward a little, turning his head so his was closer to Sans’.  _ “No need to be so nervous.” _

“m’not.”

_ “…Can tell you’re lying, when you’re anxious. It is obvious. You’re supposed to have fun.” _

Sans exhaled sharply, his eye lights flicking to the side to watch Grillby’s obscured expression. “ok?” he automatically replied, then slowly inhaled as though it would calm him.

_ “Perhaps if you made a bad joke.” _

Awkwardly, the skeleton grinned. Rubbing the side of his skull, he hunched over, unable to repress his laughter. “no fair, trying to light a match under me like that. my jokes are great.”

_ “I wonder,” _ Grillby mused, shifting slightly as something in the arena caught his attention. Sans looked up, curious when he saw the fire monster move. An explosion. He saw the way Grillby’s smile spread a little more, immensely pleased with himself.  _ “Where did your bravado run off to?” _

Sans flushed a little more at that. “no need to give me the  _ third degree.” _

_ “I also wonder how many fire jokes you’ll go through until you resort to space ones.” _

“wow. careful, grillbz, someone might hear you and put you under arrest.” Grillby gave him a perplexed look at the warning tone, and suddenly Sans felt his confidence bolster. “‘cause you’re a  _ shooting star.” _

Shortly, Grillby’s flames burst at that and he gave in to a startled laugh. That was better, Sans thought. Nothing like a little playfulness to ease the tension. He shot Grillby finger guns and winked. Prime flirting, 101. He had this.

The duration of their time spent together was much of the same. Quiet banter was exchanged, the fire monster’s curiosity burning over Sans’ reactions to his own teases and Sans resorting to a few relentless jokes.

The race below was a wild ride of wheels and commotion with little direction, but it was fun to watch for a while. Sans still felt uncomfortable in the clothes, moreso that it seemed to make it hotter compared to his regular getup. He felt his phone go off in his pocket a time or two, but declined to check it; he simply turned it off.

_ “I believe I know what the issue is,” _ Grillby offered after a while. He had snuck his hand around one of Sans’ and was tracing small circles down one of his phalanges. His expression was thoughtful but studious as he went over the fine segments of bone. Sans was trying very hard not to rattle in response, but looked at Grillby questioningly.  _ “We’re both shy.” _

Sans chuckled lowly, nodding in agreement. “yeah, too many people.” He stilled when Grillby leaned forward, his flames languidly hopping the distance between them as though in an attempt to land on his body. Sans sucked in a startled breath with the accompanying heat, finding it much different than the climate.

_ “Entirely right. We should walk around,” _ the fire monster agreed. Then he stood, still holding Sans’ hand in his own.

Sans’ breath hitched when a small flame licked up his carpals and slipped under his sleeve. Questioningly, he stared at Grillby’s face as the heat went up, curling along his bones and filling him with a comfortable warmth. It wasn’t unlike the fiery embrace Grillby had introduced him to at his sentry station. It felt a little more intimate than that.

He sighed at it, distractedly rubbing at his sternum when Grillby tugged his arm to have him stand. He did so with little difficulty, the small wisp of fire moving along one of his clavicles. It made him rattle, not quite sure what its purpose was. Blindly, Sans was led back down the stairs off the bleachers, his mind a little confused and distracted.

A pause near the end of the stairs had stolen a breath and he nearly stumbled, but Sans caught himself in time. Whatever the flame was doing had him so preoccupied that he didn’t even mind a few monsters they passed making kissy noises or whistles. It was all muted by the loud crowd.

Grillby led him down towards the streets between venues, holding his hand the entire way. Their talks were idle, Sans replying only a few times, concentrated on the flame that decided to move into his rib cage. His breaths had started to come in short huffs as the warmth flitted from side to side, jumping over his ribs and slipping in between them.

Out of the way, he finally had to stop; Sans was becoming increasingly sensitive and confused because of it. His magic at that point had started to react with the flame’s exploration and he felt hotter than he’d ever been before. In blurred thoughts, the skeleton silently admitted that he  _ liked _ the heat and probably didn’t mind this at all.

Grillby’s gaze rested upon him, smirking to himself, but he led Sans over to an uncrowded area out of view.

“i, uh…” the skeleton started haltingly. He closed his eyes and tightened his hold on Grillby’s hand. His mind blanked when the flame fluttered up his spine and he nearly let out an embarrassing noise. He caught it, but his back went rigid. “grillbz, the, uh…” Sans trailed off, not exactly knowing what he wanted to say as the flame slowly started downward in a spiral around every vertebrae.

_ “They’ve been wanting to get acquainted with you,” _ the fire monster said plainly, feigning disinterest with a mild shrug. It was  _ almost _ convincing.

He kept Sans’ hand in his grasp, but his eyes were locked upon him, watching intently. The way Sans hunched and shuddered as the small flame explored his bones was enthralling. He could see the telltale light of Sans’ soul flicker like lightning when the smaller yellow glow moved under his sweater.

It was such an impish little hellion and had pestered him to visit ever since the ferry ride. Sans leaned into his touch every time Grillby so much as cupped his face, so surely a little exploration was permitted? Then again, the absence of ‘no’ wasn’t consent, so Grillby made sure to keep the little flame from exploring too thoroughly.

“they…” Sans was rattling louder now and clutching at his sternum through his shirt, trying to stop himself. He was trying to reign in his magic, but he was obviously getting worked up about the hot touches hidden underneath.  _ “…hot.” _

_ “They aren’t causing you distress, are they?” _ Grillby’s tone was both concerned with a hint of a tease. It appeared that Sans still had the capacity to move, since he pulled Grillby around the corner and leaned against the wall, shaking his head.

“nnh… _ hah, _ nope-” he replied breathily, but he’d hunched over, still clutching at Grillby’s hand that tightened every time the flame slipped lower. In fact, it was the polar opposite of pain, he thought. “act.. active little bugger, isn’t it?”

Grillby couldn’t hide his grin when Sans made an effort to look at him. The skeleton grimaced inwardly, unsure of himself when Grillby spoke next.

_ “Fira has always been curious.” _

“you… you named ‘em?”

_ “They have names,” _ Grillby corrected matter-of-factly. His flames fluttered as though they were separate entities from him and were excited for the attention. They rolled around his visage, pluming different paler shades of orange and amber.

“i… i can’t move.”

_ “…Think you’re being overdramatic,” _ the fire monster almost purred.

Sans huffed again with a soft laugh and nodded; the flame slipped lower and seated itself into the space between the next disc in his spine, towards the middle. It was all he could do not to cling to the fire monster to hide. Everything felt hot in the best way, but his vision was also clouding, which made him a little concerned.

He trembled when Fira stayed still, the licking of heat inside his spine making him almost whine and pant with effort.

“i… think they’re d.. done.”

His soul trembled, flickering like a storm, and Sans could barely repress any noises that threatened to leave him, let alone the peculiar way his magic was amassing inside of him. Sans remained hunched as Grillby drew closer and he unconsciously grasped at Grillby’s jacket. A hand on his hip had him biting back sounds yet his entire frame was craving something… anything,  _ any _ touch.

This was ok, wasn’t it? He kind of… wanted  _ more. _

_ “Pardon my reach,” _ Grillby murmured, having leaned in close to whisper against the side of his skull. Sans absently nodded, his body tensing when the fire monster pushed past the sweater and into the free space between his ribs and illiums.

It wasn’t invasive as he thought it might be, but the light touch against his spine had made Sans jolt in surprise with an accompanying gasp.

“they have names t-too,” he said suddenly, just above a whisper. He felt like he needed to say something or tell a joke before things got too handsy in public. Not that anyone else really appeared to pay attention or seemed bothered by it; they were in the mouth of an alley on a side street that saw very little traffic. Sans hummed lowly when he felt Grillby’s unmistakable touch, flooding his bones like a brand of heat. “my, uh… my bones, i mean.”

The fire monster pulled away gently, interest bright in his eyes. Sans gave him a slight grin, still clutching at Grillby’s jacket lapel.

_ “Really.” _ His date seemed to chuckle at that, curious in his own way.  _ “…Mind introducing us..?” _

Another strange craving for touch accompanied Sans’ next inhale, his body shuddering as he felt the solitary flame slip from between his discs. He all but melted from the sensation, leaning forwards as the flame was so cruelly taken from him.

“god, yeah,” he muttered, feeling a warm hand brush against one of his bottom-most ribs. With each touch, Sans’ rib cage heaved gasps and his legs felt as though he was at risk of melting. “jeez, louise-”

_ “Peculiar names,”  _ Grillby noted, amused. Regrettably, he pulled his hand away from under Sans’ sweater but stayed close. Sans didn’t allow for him to withdraw by much.

The skeleton nodded almost absently, grinning as he pulled his date close. Grillby obliged him, dipping his head to caress his jaw with his mouth with a low chuckle. The deviousness in it made Sans’ spine tingle.

“wow.” Sans shuddered, tugging at Grillby’s jacket a little more when his date’s hot mouth found the crook of his neck and settled against the third vertebra. The accompanying warmth made his mind swim and he sucked in a sharp breath with the tingling sear of fire against bone.

The heat seeped down to the marrow, making his soul thunder. Unable to help himself, Sans pushed his phalanges up to hang around the back of Grillby’s neck. Yeah, he liked this. Uh oh.

“wow, martha-”

He felt the fire monster’s mouth curl into a smile against his neck and he tilted his skull to invite more dizzying touches. Grillby finally let go of his other hand and it crept up Sans’ side, leaving tingling pulses that had Sans’ mouth hanging open and gasping. Grillby pulled one side of his collar down for better access and turned his head to press against him.

The skeleton leaned forward, unable to mute an appreciative moan as he felt Grillby’s hot tongue evaporate any lingering moisture in that spot, flooding into the cracks. It ignited him and Sans experimentally traced his fingers along Grillby’s neck, eliciting a subtle shiver through the fire monster’s body as a reward.

“holy mary-”

It appeared that Grillby favoured the spot and Sans yearned towards him, his teeth pressing together with another sharp inhale. “jehoshaphat-”

Sans felt it when Grillby grinned and laughed against his neck again, awkwardly. Grillby’s mouth moved back up an inch, sighing against the singed bone.

_ “Think I like ‘Mary’ best,” _ he breathed. Another shudder of anticipation ran through Sans’ body as Grillby’s mouth moved against him.

“thought you liked  _ me,” _ Sans joked, his breathing hitching more as he fought back a moan that he couldn’t quite mask.

Cupping one side of his skull in his hand and gently butting him with his face, Grillby smirked and silently notched another point in his favour.  _ “I think I can tolerate you.” _ Witnessing Sans’ grin tighten with a laugh, he playfully agreed.  _ “Besides… those aren’t even real names.” _

Sans’ vision was still cloudy, but he grinned all the same. That’s when he realised a little dimly that it was  _ smoke, _ and it was coming from his left side -- where Grillby had kissed his neck. He blinked at the fire monster, then Sans locked his arms around his shoulders so Grillby couldn’t escape.

“who says,” he asked daringly.

_ “Perhaps we can ask that picture of a skeleton that you were so invested in days ago.” _ With that memory, Sans flushed. Grillby appeared even more amused at the reaction.  _ “What? Is that what makes you blush?” _

“if we kiss-” Sans’ mind almost flatlined with the proposition, but he managed to continue, “-can you drop it..?”

Grillby made a show as though weighing his options, but his mouth was curled into a sly smirk.  _ “…Believe there are some labels absent that require… clarification.” _

Sans let his head fall forward against Grillby’s chest in resignation, while the fire monster took advantage of the opportunity and dropped a gentle kiss on top of it.

**Notes for the Chapter:**

> Hey look, they finally have a date!


	9. Chapter 9

**Summary for the Chapter:**

> Tremors rumble through the caverns in Waterfall. The ferry ride is dangerous for once, and Sans once again fails to warp them away. Grillby ends up getting injured, and Sans reaches his limits.

They ended up wandering around the venues for a while until they ran out of things to do -- namely things that didn’t involve finding a secluded area out of sight. There were booths that they could play games at, some small shops to poke through and a live performance featuring some Waterfall monsters doing an interpretive dance. When it got late and the races had ended, they decided to head back.

On the ferry, Sans eventually calmed down and recounted what had happened in his mind. The date had gone well; Grillby seemed to enjoy the area, and Sans had too. He’d found that no matter how Grillby tested how far he could go with him, Sans wanted more of the same. Essentially, they were playing on equal terms.

His thoughts wandered a little, the rush of water around them making the fire monster inch his hand towards his own again. Less hesitant than before, Sans rested his hand over Grillby’s with a tired smile. The day had been long, but fun.

Sans stole furtive glances at Grillby the entire time, the warmth in his chest never quite at rest. Grillby seemed to tense throughout their winding journey on the river from Hotland to Waterfall, and scanned the ceiling far above. His fires shuddered and were close to his body, making him appear dim and even smaller.

“something on your mind, g?” Sans eventually enquired, watching the space above them. He didn’t see anything, but it was likely the fire monster just felt nervous. The ferry ride was slower than their previous trip.

Suddenly, Grillby’s flames plumed, then dimmed again. Sans knew that it was a nervous tic of sorts, so he gently patted Grillby’s hand.

_ “…Something is moving.” _

“tremors?”

Grillby didn’t respond, but when he adjusted his glasses, his expression was unreadable. Several moments passed in silence so much that Sans thought maybe he didn’t want to talk about it.

Small pebbles fell from above along with a faint dribble of dust and water. Frowning, the skeleton looked up again to try and see what Grillby saw. There wasn’t anything, but he could detect a faint rumble from somewhere in the distance.

_ “Not tremors,” _ the fire monster finally said. His voice had a raspy note -- as though he was on edge. Small glowing flecks of embers popped away from his body and floated away, only to be extinguished in the humidity.

“i can’t see through this. are you gonna be ok?”

_ ‘Tra la la~ The waters are wild today. That’s bad luck…’ _

Sans shot the river person a dirty look, but the figure remained turned away from them, blocking the immediate view of their destination. A few more pebbles fell from the ceiling, accompanying a low rumble that made the waters shudder around the craft. It was moving slower.

“hey, uh, can we go faster?” Sans called to them, trying not to feel nervous. With Waterfall recently notching last on his most favourite places in the Underground and with Grillby’s added apprehension about the surrounding waters, Sans really didn’t want to linger any longer than they had to.

_ ‘Tra la la. Tri li li. Tre le le.’  _ The ferry’s speed remained the same.

Groaning softly in dismay, Sans hooked his arm over Grillby’s shoulders. He was  _ very _ tense, but he knew Grillby appreciated the effort.

Sans looked inward. His buffer was there, however small it was, but he would only be able to warp them once and not for that large of a distance. Sans looked down the canal, shifting slightly so he didn’t pull Grillby towards the side of the boat.

He still couldn’t see anything, but the fire monster’s mounting panic was enough for him to decide that warping them was the best option. Surreptitiously, he gathered his magic and slipped his hand into Grillby’s, hoping it wouldn’t garner suspicion.

As luck would have it, Sans was able to reign in a lot more energy than he had on their previous trip. He scanned ahead of them; there were no familiar outcrops to land on, so he figured the wishing room had to be the safest and driest area as a landing point. He’d worry about the details later.

The wisp of cyan and gold flickered in his left eye, betraying his intent. Grillby’s entire body stiffened, a protest forming when he felt the surge of wild energy flare up next to him. Then it suddenly sputtered out, punctuated by Sans’ shaky breath. Grillby’s soul clenched with fear.

They hadn’t gone anywhere and now Sans leaned against him, his breaths harsh as though the effort had been painful.

_ “Why did you..?” _ There was an added panic to the anger in Grillby’s voice.

Sans huffed shortly, not immediately answering but he managed to shakily push himself upright. Why hadn’t it worked? The buffer was almost gone, with four points remaining. His magic felt torn again, but they hadn’t budged an inch. It had been a gamble and Sans  _ lost. _

_ ‘Tra la la~ Refrain from spatial and temporal manipulation during the ride.’ _

Sans paused with the river person’s words. He stared at their back as they continued on, armlessly steering through the canal’s pitch darkness. He purposefully avoided Grillby’s face, just knowing if he saw the oblique concern there that he’d push the fire monster away. It’d be a horrible end to the day after such a date, after all.

He settled a little more next to Grillby, propping his arm around his warm shoulders. Sans clasped his other hand on Grillby’s, ignoring the puzzled repetition of  _ “Temporal..?” _

It wouldn’t do to give it an answer, Sans thought. He just concentrated on regulating his breaths so he didn’t look as bad as he felt.

The waterways were beginning to become a little wilder. First the craft bobbed as though something had disturbed the river’s currents further ahead, then it cut up into choppy waves. The river person remained as nonchalant as ever, humming an eerie tune. Having had enough, Sans went to stand up and kept a hand on Grillby’s shoulder to steady himself.

_ ‘Dancing on a boat is dangerous. But good exercise…’ _

Sans took that as a warning to sit down again and did. He offered the fire monster a reassuring smile, though it must’ve looked more like a grimace, since Grillby returned it with an agitated scowl, obscured by his low flames.

“you can’t fault me for trying,” the skeleton shrugged. He dug around in his pocket for the piece of jerky, hoping it would ease his exhaustion. He tore off a piece and offered it to Grillby, who slowly shook his head in silence.

The leaden awkwardness came back with full force, though for different reasons. Sans held his head in one hand after finishing his jerky and glared off into the distance where larger, choppier waves formed. He could feel his soul sink with building worry.

He paid attention to the river person a little more now, as their singing picked up with a particularly nasty set of waves. Grillby kept a hand on his and with every rock of the craft, his grip noticeably tightened.

A few larger rocks fell from the ceiling and landed in the water next to Grillby, splashing him. The fire monster grew considerably agitated by that, and even though he assured Sans that he was unharmed, it threw up a spray and steam filled the tunnel.

Grillby only let go of his companion’s hand long enough to rub his own together with a hiss. His left hand crackled and burned a deep auburn, having been briefly extinguished until the small flames from his other hand jumped over to rekindle it. Despite the immediate attention, the flames remained low.

The next wave was considerably taller. It crashed against the side of the ferry and Sans swore loudly. Even though he was a head shorter than Grillby, Sans made a valiant effort to block him from the crashing wave. In a sense, it had worked; Sans took the full brunt of the splash and Grillby had lowered his temperature quickly enough to avoid something catastrophic.

“that’s  _ it-” _ Sans sputtered angrily at the river person, who hummed idly through another wave. Marsh water had filled his skull and Sans parted his teeth to allow it to drain with a disgusted shudder.

He witnessed a few sparks come off Grillby, then a high red plume jettison around him, scorching the ferry’s floor and brightening the area considerably. The temperature hiked up around them and soon the entire craft was covered in a dense fog that slowly loomed over them as it moved ahead.

Grillby was starting to panic.

_ ‘Tra la la~ Another waterfall. Be careful.’ _

Sans’ eye sockets hollowed out when he saw the deluge arcing before them. He had little time to think as he automatically drew up his magic, gripping Grillby’s hand tightly to keep him close. In a roar like thunder, more rocks fell from the ceiling and onto the ferry and around it, kicking up more water as the waves crashed closer.

Grillby’s breaths were quick, his eyes bright and wide as his fire whipped around him, claustrophobic in the small area. He seized Sans with both hands when he saw the wave loom above, just starting its descent to crash over them. The crackle of Sans’ magic whipped up, constructs slamming into place just in time.

It would’ve been close. Sans was left panting harshly with his left arm raised high above his skull, but he’d managed to conjure a huge cage of bones in quick succession to block most of the water from hitting them. It wrapped around them like a shield of bone, leaving little space between the craft and their bodies. The calcified constructs wove so tightly together that hardly any water trickled through.

“i should’ve saved that jerky, heh,” Sans gasped. He rattled as he settled back down to the bench, his hands just as shaky as the rest of him, if not more. He took a few more calming breaths before he added a little bitterly, “what a way to end a day.”

The rest of the ride was nerve-wracking, but once they made it past Waterfall, it appeared that they were in the clear. They couldn’t have left the ferry any faster even if Sans warped them off of it.

Grillby kept quiet, calmer now that they were in the safe grounds, and Sans bit his figurative tongue in order not to cuss out the river person entirely for such reckless driving. It could have been worse; it could’ve been  _ much  _ worse. But still, Sans watched as the craft drifted away, leaving them in the snowbank north of Snowdin.

Grillby was still holding onto his left arm. At a glance, it looked like his colouring and flames were back to normal. Sans watched them for a moment before he realised that he was staring. Awkwardly, he sent Grillby an apologetic smile.

_ “…Look tired,” _ the fire monster finally said.

Sans noted the concern and nonchalantly rolled his shoulder. “m’always tired.” He paused, then glanced at Grillby’s left side. “how’s the hand?”

Grillby raised his hand to inspect it; the fire was low, to a mere shimmer close to his form now that Sans saw it up close. He grimaced slightly -- or at least Sans  _ thought _ it was one. Sometimes it was hard to tell. Sans gestured for him to hold it out. Hesitant, Grillby did and Sans held it in both of his hands.

The embers were low and fluttered slowly like a waning fire. It was spotted with the colour of dying coals and Sans couldn’t help the twinge of regret that hung in his soul as he cupped the hand.

_ “It will rekindle,” _ Grillby reassured him quietly, as though he sensed Sans’ distress.  _ “It only looks bad.” _

Sans turned over the hand in his grasp and noted the pained twitch. Grillby failed to repress his reactions when he brushed his bony fingers against what looked like water burns, as odd a thought that was. The injured hand didn’t feel as warm as Sans remembered, either.

“looks like it hurts though,” he muttered, clasping both of his hands over it.

Even though it wasn’t one of his strengths, Sans intended to alleviate the pain and heal it as best as he could. He stepped closer so Grillby would relax, letting his hand lay in Sans’ grasp. Sans felt his gaze on him and smirked apologetically in return. He wanted to make this right.

“i’m kinda bad at this, but i’ll try. in the meantime, you tell me what you saw.”

Grillby shifted in place, then turned his head towards the river in thought. There was a prolonged period of silence before he said anything, until he felt the gentle tingle of Sans’ magic flow through into his fingers and palm with its healing touch.

_ “Thought I saw… roots.” _

Sans frowned, his eyes closed in concentration as he drew on more of his magic. It was a good thing his levels were all over the place lately, but drawing on it now felt like it was unravelling something from deep inside of him, like a sweater caught in a wheel.

_ “Could be… tremors. And in my panic, perhaps I imagined it.” _ Grillby sighed, bringing his other hand to cover the lower half of his face.

For a fire monster, Sans’ way of healing was peculiar, tingling and soft. It was gentle and slow and while not painful, reminded Grillby of being doused. For some reason ‘cold’ came to mind, even though the chilly climate around them had little effect on him and he never really could associate it with the word.

Sans nodded to show that he understood, knowing it was his job as a sentry to report any suspicious activity to Undyne -- even if it was likely that she already knew. Now  _ that _ was a conversation he didn’t want to have; it would likely turn into a whole different one, knowing her. Sans exhaled softly as his magic regrettably began to wane.

“guess that’s it,” he muttered in agreement, cracking an eye open to gauge his attempt. For a moment, his vision was blurry but he powered through it. “it looks like my  _ handiwork _ really got through here.”

He smirked when he heard Grillby’s resigned sigh, and Sans carefully unclasped Grillby’s hands from his own. They looked a little brighter at least, although he wasn’t sure if that was a good sign or not. Grillby didn’t appear to be in any more pain, unless the guy had a high tolerance for it.

He watched as Grillby flexed his fingers, his hand only shaking a little. Sans let his own drop to his sides, his arms heavy after putting forth so much effort. It almost felt as though his legs made him lean too much to one side, too.

He gave the fire monster another apologetic grin with a shrug. With the date at its close, Sans wasn’t quite sure how to say goodbye. Alphys’ cartoons usually had awkward goodbyes or… a kiss goodnight.

_ Oh boy. _

_ “One for the road?” _ Grillby suggested after a pause, having watched Sans shuffle where he stood. Sans’ grin twisted into a shy grimace and his magic gave off a delightful subtle glow again when Grillby stepped forward, closing the distance between them.

Sans was sure that whatever strength he had left was bolstered by the gentle kiss against his mouth. When he closed his eyes and leaned in, his soul started to nervously flip. It’d been much too short, but it was soft and sweet. He hummed quietly, unable to help but notice the pleasant feeling that crept back into his rib cage, brightened by the gesture. Sans fought back a protest when the kiss ended and he reopened his eyes.

Grillby’s face had cleared a little so his smirk wasn’t quite so secretive, and the fire monster patted the side of Sans’ head with his good hand. Then he sighed wistfully, a light trail of steam catching in the air with his ambient heat.

_ “…Here I thought I was winning.” _ He seemed almost disappointed. Sans shot him a perplexed look and Grillby’s smile broadened a little more.  _ “7 to 6, Sans. You’re in the lead.” _

Sans made a sound as though he was clearing his throat and absently scratched the side of his jaw. “do you mind, uh… running the rules by me again?”

Grillby didn’t hold back his chuckle.  _ “And what fun would that be?” _ Sans’ bemused expression was adorable, so he left it at that, giving the bony cheek another gentle pat for reassurance.  _ “…Had a good time.” _

Sans’ blush broadened despite himself, his voice dying when he felt the urge to say “me too”. He watched Grillby go with a slight wave, and stuck his hands into his pockets until the fire monster was well on his way. When Grillby eventually turned out of view, Sans slouched his shoulders with a deep exhale, wanting nothing more to lie down and nap for a few days.

Habitually, he pulled out his phone to check his messages. With the device powered off the entire time, Sans actually forgot that he’d brought it with him. It was a good thing Alphys had waterproofed it; it wouldn’t have survived the torrent of water otherwise. It booted up just fine -- and several more messages popped up, along with five missed calls from different people. 

He sighed again and pulled up the messages from his brother, ignoring the rest.

Papyrus (Last message received: 3:52pm);   
\- OH MY GOD   
\- SO APPARENTLY I MERIT A PAYCHEQUE?   
\- ALSO, APPARENTLY WHETHER OR NOT WE CATCH A HUMAN DOES NOT AFFECT OUR PAYROLL. WOWIE!!   
\- AND… FOR SOME REASON, UNDYNE’S HERE?? WHEN YOU GET BACK, COME HOME RIGHT AWAY!   
\- SHE MENTIONED THERE HAS BEEN EARTHQUAKES LATELY IN WATERFALL. BE CAREFUL ON THE FERRY!

Thoughtfully, Sans scratched his head. The last two messages had been sent a few hours ago and he groaned softly, wishing he didn’t have to socialise after such a full day. Sans would’ve loved for nothing more than to curl up in bed, dreaming sweet dreams of warm, soft kisses.

Without thinking, Sans pulled together his magic to warp home. An odd sensation reverberated throughout him when he missed the landing, as though there was a shock to the end. Sans ended up grasping the air for a moment and lunged against the nearest building to stabilise his footing. Something inside of him twisted inwards -- and it was  _ painful. _

Ok… so maybe he used up more magic than he’d thought. Sans hazily looked around his current location, taking in the familiar setting. He’d missed his landing by a few feet and was right by the shed Papyrus kept locked up -- in case he caught a human. He weighed the pros and cons of going inside it to nap instead, but Sans ended up dragging his feet through the freshly fallen snow to the doorstep.

For a moment, it felt as though he couldn’t draw in breaths and the resulting confusion made his mind swim. Sans grasped at the porch column, nearly taking off half of the stringed lights in the process as he lost balance. Papyrus was going to be mad, he thought dimly as he tried to keep himself upright. He didn’t even realise that he’d sunk to the ground and the door had opened with explosive force.

For the most part, he was eventually able to clarify things. Sans recognised his brother by the colours he commonly wore, but little else. It would’ve surprised him to see Papyrus out of his battle body, had he considered thinking about anything else besides wanting to sleep.

Yeah, he definitely pushed himself to the limit.

“OH MY GOD! SANS!” his brother boomed, then stooped down low to pull him off the porch. Papyrus slung an arm around Sans’ shoulders to keep him upright, but thought better of it and pulled Sans close to carry him through the front door instead. “YOU’RE SOAKED! WHAT HAPPENED?”

Sans muttered something inaudible against his shoulder, barely aware of the question.

“CLEAR THE COUCH, UNDYNE,” Papyrus called inside, approaching quickly after he had slammed the door shut. It roused Sans, but not by much.

Undyne remained seated but scooted over, covered in blankets with a bowl of chips in her lap. Her good eye widened when Papyrus carried his brother into the living room and sat him down next to her, then peeled off upstairs.

“Jeez,  _ you’re _ looking lively,” Undyne muttered to Sans, who was unresponsive, his eyes half-closed. “You didn’t get into any trouble, didja?”

Sans shifted slightly when he heard the familiar voice and shortly after, his eye lights faded out. Undyne drew herself up with a grimace and gave his shoulder a brisk shake.

“HEY!! Sans, keep awake for a sec, Pap’s comin’ back.”

“I’M HERE!!”

Papyrus barrelled down the stairs with an assortment of towels and blankets folded in his arms. When he approached his brother again, Sans shifted a little more, uncomfortable. Papyrus moved him to wrap towels around and underneath him, essentially transforming Sans into a bony cocoon.

“I WARNED YOU, BROTHER. I TOLD YOU.”

“HEY!! What the HELL is going on?” Undyne demanded, her single eye flicking from each of them.

“m’just tired,” Sans muttered, and closed his eyes as Papyrus fussed with the blankets.

“YOU BURNED OUT,” Papyrus scolded him, his voice raising half an octave higher than usual. In a matter-of-fact tone, he added, “COMPLETELY FRIED!”

Sans couldn’t help but laugh softly at that, cracking an eye open to blearily look at his brother’s face. “heh, good one.”

Papyrus twitched at what he thought was his brother’s usual evasive behaviour, then he realised just why Sans was struggling to keep awake. “OH. OH DEAR.”

Sans tried to give him a dismissive wave, though he was effectively trapped between what was probably four blankets and three towels.

Undyne’s gaze shot to Papyrus, still not comprehending the situation. Papyrus sighed and knelt in front of Sans, resting each of his bony hands upon his brother’s blanketed shoulders.

“TELL ME EVERYTHING, BROTHER,” he said, his voice softer. Undyne’s brow arched skeptically with the even-tempered way in which he spoke. “EVERY INSTANCE WHERE YOU EXPENDED MAGIC.”

Sans shifted again, uneasy. The lights in his eyes dimmed as he raised his head to look at his brother’s face. If he were of half a mind to bother, he wouldn’t have said half the things he was about to.

“mornin’… shortcut.” He was working with the bare minimum, at least.

Papyrus frowned, not fully understanding what Sans meant by that. But then again, his brother never alluded to how he managed his ‘shortcuts’, only that it took a bit of magic to do. It’d been so long since Sans had started using it as an excuse that Papyrus stopped asking about them. He even forgot they were a thing until recently.

It took Sans several moments before he spoke again, his voice dropping in register. “date stuff. tossing game. lost a bunch. it was… fun.” He paused again, his head nodding forward. “sleep now..?”

Papyrus shook him slightly and Sans exhaled as though in pain. His brow furrowed. “TELL ME WHAT ELSE!” Papyrus demanded, his voice earnest. “THAT CANNOT BE ALL!”

Sans attempted to look at him dead on, but realised he had little energy for anything else. Papyrus was a blur to him. “…back home.”

“YES?”

“shortcut,” Sans mumbled thickly. His words were difficult, as though he was attempting to remember how to speak in an entirely separate language, “…tried takin’ g with.”

“G?” Undyne enquired, hanging onto every word.

“HE MEANS GRILLBY,” Papyrus said absently, ignoring her surprised look.

“THAT’S the date??” she said suddenly, grinning wide and showing off her fangs. “Wait… that flame guy??” She’d been told about the date, just not  _ whom  _ it was with.

“…didn’t work,” Sans finally finished. He felt the peculiar probe of magic against his soul and instinctively tried to push out against Papyrus, but his arms were buried in the blankets. “don’t.”

“YOU SEEM OK, AT ANY RATE,” his brother muttered. Then with a heavy sigh, Papyrus pinched the bridge of bone between his eyes in thought.

Sans’ HP rested at 3, much lower than that afternoon. Had it been 8, or maybe 6? After the commotion around Undyne’s visit to Snowdin and her constant barrage of questions, Papyrus found that he simply couldn’t remember.

“IS THAT ALL?” He gently nudged Sans’ shoulder. His head had fallen forward, his eyes closed as though Sans was finally done fighting off sleep.

He didn’t reply for another few minutes, so Papyrus exhaled, trepidation broiling up inside of him like a loose canon. Undyne looked on the verge of asking something, but stopped when Sans spoke up;

“there was an earthquake, i think..? g said… he saw roots moving. tell undyne, ok, bro…”

“I’m right HERE, Sans?” Undyne nudged his shoulder from his other side, her eye narrowing with suspicion. She watched Papyrus, whose expression was concerned. Carefully, he gently tapped the side of Sans’ skull to rouse him again.

“IS THAT ALL, BROTHER?” Papyrus asked one final time, finding both comfort and concern with the subtle way the blankets rose and fell with his brother’s breaths.

Sans couldn’t help a small smirk at the memory, though it was difficult to keep awake now. “saved ‘im.”

“HOW?”

“bone zone.” His smirk widened a little more.

Undyne pressed her hand to her face with an audible smack. Even exhausted to the point of falling asleep where he sat, the guy could still make jokes. For once, she held her tongue, if only for the reason that Papyrus looked so worried for him.

Sans seemed to recognise it. A little, at least. “lotta bones,” he clarified dimly. “lotta, lotta bones.” Papyrus waited, as he seemed to know that Sans still had more to say. He wasn’t disappointed. “g got hurt… so i healed ‘im.” Sans paused again, his face contorting into a grimace of self-criticism. “i suck at healing.”

“YOU DEFINITELY NEED MORE STAMINA FOR IT,” Papyrus chided him softly. “IS HE OK? SHOULD I GO OVER AND CHECK ON HIM?”

“he’s fine,” his brother whispered. “one more… shortcut.  _ missed.” _ His next inhale was sharp and with it brought on a wave of dizziness Sans had to fight. “…feelin’ it.”

“AS YOU WOULD! I DON’T KNOW THE CIRCUMSTANCES OR EVEN THE WHEREWITHAL YOU HAD TO PAY FOR ALL THAT MAGICAL EXPENDITURE TODAY, BUT CONFOUND IT, SANS! I WARNED YOU THIS MORNING AND I’LL WARN YOU AGAIN. ESPECIALLY WITH ALL  _ THIS-” _ Papyrus stopped and gestured both pointedly and vaguely around his brother, his movements agitated. “-GOING ON, I EXPECTED YOU TO TAKE CARE OF YOURSELF! I EXPECTED YOU TO HEED MY ADVICE! RECKLESSLY BLOWING THROUGH YOUR RESERVES LIKE YOU’RE A BOSS MONSTER!? HONESTLY! YOU’RE NOT GOING TO LEARN YOUR LIMITS IF YOU BARREL THROUGH IT LIKE NOBODY’S BUSINESS! IT’S FOR YOUR OWN DAMN GOOD, SANS, IT’S-”

Papyrus stopped when he realised that Sans had given up the ghost. His head was tilted offside and his teeth were parted, eyes closed. The bone around his eye sockets looked stressed again and even a little darkened, and Papyrus knew Sans probably felt a lot worse than he appeared. He always put up a strong front, even when he didn’t need to.

Even with him.

Several moments passed before Undyne thought to speak, her head reeling. “You got  _ backbone!” _

Papyrus straightened his spine, snapped from inward thoughts when he heard Undyne’s booming voice. He stammered apologetically while Undyne laughed at his reaction, harsh and raucous. Papyrus made excuses but she shook her head with a shrug.

“Far be it from me to lecture ya, Papyrus. Is this doofus gonna be ok, or should I call Alphys, or a healer, or..?”

Papyrus sat on the floor next to the couch and stared at Sans, then gave her an upbeat smile. It was difficult to do, a little forced and stiff, but he somehow even managed to give her a thumbs up.

“HE’LL BE JUST FINE! MY SWEATER, HOWEVER…” His eyes narrowed with baleful conviction, as he’d noticed a few burned areas around the collar and back panel. It was obvious things got hot under the collar. “…WILL NOT BE. I EXPECT THE DATE ITSELF WENT WELL!  _ VERY _ WELL.”

**Notes for the Chapter:**

> Sans is winning: 7/6.  
> The basis for practising magic is so that this kind of thing doesn’t happen, Sans. A steady lead-up to the limit would have allowed him to know his max magic output better. Doing this so often can be debilitating and even dangerous, which is why Papyrus was upset. C’mon, Sans!


	10. Chapter 10

**Summary for the Chapter:**

> Sans remembers an authoritative figure in his dreams. Papyrus learns of his bad habits. Meanwhile, Undyne is stuck babysitting, and as a result pays Grillby’s a visit. It does not go as planned.

**Notes for the Chapter:**

>  **content warning(s):** vomit mention, reference to past child abuse

Sans would’ve been more concerned if he had been dreaming lately, but he wasn’t entirely sure if what he was experiencing was a dream or not. It certainly wasn’t a nightmare. His nightmares tended to have themes and general ideas that blended together. The situation he was in now didn’t seem very dreamlike, but he was certain that it hadn’t happened before. In every way, it was perfectly mundane while being completely baffling at the same time.

He was back home; starting university, to be more accurate. Papyrus wasn’t with him. He was too young to go to school just yet. Sans was following someone; an older, taller monster whose head was obscured simply by shadow or because Sans couldn’t care to look.

His voice was familiar as he talked, and when he did it was quick and precise. He was curt and to the point, and didn’t pull his punches. His accent was acrid and vile, a stark opposite to Sans’ own, and it had a particular drag between words and a lilt against the hard vowels. It almost sounded stilted; that is, if the person wasn’t so self-assured and pragmatic. It was as though multiple tones were housed in one voice.

Sans only knew that he hated him beyond any measure of a doubt.

“We have not finished our conversation,” the other monster had been saying. Sans remained silent but fell into step behind him. He just knew he had to follow closely, otherwise he’d be subject to harsh reprimand. “You recall.”

“sure,” Sans automatically replied. Something in his rib cage twisted and he idly rubbed the spot. Dimly, he recognised a thin horizontal pinstripe across his shirt that peeked out from under his lab coat.

“Stop your fidgeting.”

“m’not.” Deliberately, he scratched again.

“And stand upright.”

“ok.” Feeling rebellious, Sans made sure to slouch his shoulders a little more.

“It is either ‘yes’ or ‘understood’,” the older monster chastised. He stopped and whirled around, but something prevented Sans from viewing his face. He felt as though he already knew it, though. He hated the sneer he could definitely see. “If you are going to traipse into my work this way, I expect you to conduct yourself in a less shameful manner.”

Sans felt the twist of pain again, coupled with disappointment and anger. The only reason he was doing all this was for Papyrus, whom he had to leave at home with a neighbour. He forcibly corrected his posture, though Sans knew this person would criticise him as soon as he saw something out of place. He  _ always _ did that.

It awoke something at the back of his mind, sparked off and fired into another direction. Confused, Sans stared forward. It had been a passing thought, but it was right, wasn’t it? The adult monster approached him and Sans automatically took a step back. It was a reflex, like Sans expected to be struck.

Instead, his coat and shirt were adjusted with firm and harsh movements. All the while, Sans scowled at him and tried not to jerk forward with the tugging. A set of hands rested on his shoulders, the gesture oddly gentle. Another pair fixed the safety pins that kept his rolled up sleeves in place with an equally baffling amount of care.

“Don’t give me that look.”

“can’t say i got any choice, pops.”

“‘Have’. And no, I suppose not.” The adult paused, and for that moment Sans felt the glare just as much as he didn’t see it. “Another thing: you will not address me as such any longer. It is either ‘Sir’, or ‘Doctor ▟▓▒st▚r’ while you conduct your studies here. I will not have you tarnish my good name by calling me by such useless titles, but you should consider yourself privileged to work alongside myself and my associates.”

Sans’ permanent grin tugged into a sneer as he looked up at the taller monster’s visage, obscured and towering above him. The bright lights ahead in the corridor shrouded his face in shadows, making his father appear almost menacing.

“oh, do i  _ ever.” _

“We can do without the sarcasm for at least one day, boy.” That familiar warning was something Sans knew all too well and he couldn’t help but shrink down at the tone. Another set of hands gently pushed at his back when the doctor turned to continue down the corridor. “Now come with me. I expect you to heed my warnings. Today the King will be gracing us with his presence. I expect you to behave favourably; which means no swearing-”

“well, fuck.”

“-or fidgeting, or staring, and certainly none of your obstinate pranks. He is an incredibly powerful Boss Monster of whom I hold in high regard and I will  _ not _ tolerate your embarrassing behaviour in front of him. We will be discussing the CORE’s future and your integral role in its development.”

That was the only amount of praise Sans ever got; veiled disappointment and condescension. He was a tool that could be used, expended until recharged. At least Sans knew he was smart enough to be tolerated in the long run.

The ticking of a familiar clock pulled him back to consciousness, heralded by the static of an untuned television. Sans blearily looked around for a moment as he collected his bearings, torn from his dreamlike memory to the world at large. His eyes eventually focused on the fact that the couch’s arm was less like a pillow than he’d originally thought, and he was wrapped comfortably in a mountain of blankets.

It was late at night. Alongside the snores coming from Undyne’s side of the couch, a little noise came from the direction of the kitchen and a soft glow of light poured into the dark living room from its doorway. Despite his efforts, it took quite awhile for Sans to untangle himself from his cosy entrapment.

He still felt raw and unstable on the inside, but at least he could string together coherent thoughts and shuffled his way to the kitchen without too much wobbling. His brother was busy dishing out meals into containers for the next few days, his expression grave as he worked. He looked so out of place without his battle body, Sans thought, though he supposed that they were now a matching set.

Papyrus looked up when he saw Sans enter the doorway to wordlessly lean against the entrance.

“YOU’RE AWAKE,” Papyrus said, his voice low. He had long since learned to keep quieter whenever Undyne came over and ended up spending the night. “I EXPECTED YOU TO SLEEP CLEAR THROUGH UNTIL MORNING.”

_ I expect you- _

Sans’ nonexistent gut twisted when Papyrus dropped a ladleful of sauce over each portion with a little more force than what was probably necessary. Bits of orangey-red splattered everywhere. Sans could tell whenever Papyrus attempted to hide the fact that he was upset.

With the dreamlike memory still fresh in his mind, Sans watched as his brother moved around to the sink and rinsed off the ladle, then set it neatly into the drying rack.

“you sound like him.”

After a pause, Papyrus sent Sans an odd look over his shoulder. “I DON’T THINK I SOUND ANYTHING LIKE MISTER GRILLBY. HE’S FAR TOO QUIET, FOR ONE.”

“not him,” Sans clarified with a wince. Then he decided that it was probably best if he didn’t bring  _ him _ up. Even if ‘him’ referred to a vague collection of unpleasant memories that made him feel small and worthless.

But it was too late. He had apparently caught his brother’s interest. Calmly, Papyrus manoeuvred around the counter and pulled out a chair, beckoning to Sans. His gestures seemed a little calmer as Sans shuffled over, still on the cusp of both waking up and recovering. Once seated, Sans slouched over the table and waited for the inevitable scolding that he would receive.

Instead, Papyrus moved back to the counter to grab a notebook and returned to push it in front of Sans. He then opened it to a page where he’d drawn up a list, and Sans felt a twinge of guilt when he realised that it was a list of magical expenditures from the previous day.

Papyrus left it there for him to ponder over and busied himself by pouring a bowl of cereal, and once more returned to set it in front of Sans, without milk. Sans winced as he grabbed a small handful and popped some into his mouth. It was crunchy, but he reasoned that it was better than being offered pasta again.

“I WANT YOU TO LIST OUT ON A SCALE FROM ONE TO TEN-” Papyrus gestured to the open page and took a pen from the counter. “-PRECISELY HOW MUCH MAGIC EACH ACTION TOOK. WITH TEN BEING THE HIGHEST EXPENDITURE, AND ONE BEING THE LOWEST.”

Sans remained quiet and eyed each item on the list with growing discomfort. The way Papyrus phrased his request made him feel bitter and smaller than before, but he complied, knowing that his brother was only concerned. He started with the ones he knew, scrawling his unkempt, bulbous handwriting next to his brother’s righteous, spidery script.

He didn’t immediately address the shortcuts, but figured it was maybe… eighty bones for the defense cage? Sans was terrible at healing and rarely did it since Papyrus never got injured. He tapped the pen against his teeth in thought, staring at the remaining choices after writing ‘negligible’ next to the tossing game at the arena’s arcade.

Shortcuts.

He rubbed at his skull, drawing a blank on how to quantify what it took to make one. It wasn’t quite magic, but at the same time it wasn’t  _ not _ magic. He hummed softly and stopped the tapping when Papyrus peered over his shoulder. It reminded him of a much taller monster looking over his work when he was a lot younger, only with less hands.

Less hands. Well, that was a strange thought.

“what do you think, teach?”

Papyrus ignored the nickname and frowned as best as he could. Sans offered him a coy smile in return. Maybe he wouldn’t ask too many questions about the shortcuts, after all.

“WHAT KIND OF CONSTRUCT DID YOU MAKE?” Papyrus pointed to his not-so-serious answer of ‘80 boners on a boat’ with a single digit, ignoring the childish joke. “AND WHAT WAS IT FOR?”

“g-man was gonna get splashed big time, so…” Sans shrugged, scratching the back of his neck under his collar. With a frown, he pulled out a leaf that had stuck to his spine, then let it unceremoniously drop to the floor. “…i did a cage-bundle?”

“YOU COULD HAVE SET IT UP MORE LIKE  _ THIS _ AND WASTED LESS ENERGY-” Papyrus took the pen from him and sketched out a ring of twelve bones with arrows indicating motion in a rotation. It appeared to be a kind of shield. Leave it to his brother to come up with something so ostentatious. “IT WOULD’VE BEEN MORE EFFICIENT!”

“i literally had no time to think,” Sans replied lamely.

“YOU DIDN’T ANSWER THE SHORTCUT LEVELS.”

“nope.” Sans avoided Papyrus’ pointed look and decided to grab another handful of cereal. He chewed it deliberately, making crunchy noises just to mess with him. Papyrus knew what he was doing and glowered down at him, like he was fighting every urge to take the cereal away.

“ok, fine. say… one shortcut, just me, is… usually a one, lowest. easy-peasy.” Sans shrugged, still avoiding his brother’s look. “and taking someone with… maybe thirteen?” He chewed more cereal, crumbs dropping onto the page. Papyrus’ eyes narrowed with suspicion while Sans ignored the glare.

“THIRTEEN.” There was a challenge to the words.

“sure.”

“I ONLY MADE THE SCALE OUT OF TEN, SANS,” Papyrus indicated irritably, but he drew out a new graph for the overestimation anyway. He was suddenly more serious than before and paused, watching as his brother ate. “HOW MANY TIMES DID YOU DO THAT TODAY?”

“once,” Sans replied with another shrug.

While he remained quiet, Papyrus quickly realised the three point discrepancy between what his brother’s health was, compared to when he got back. He knew that if pressed on it, Sans would simply stop talking, but the nature of the shortcuts worried him. If it took HP away with Sans’ poor health, how long would he push himself until he came back to Papyrus as a dust-covered jacket?

Papyrus didn’t want to think of that. He had to broach the subject another time. It had been the most information he’d gotten out of Sans about his shortcuts and Papyrus knew that his brother was still exhausted. He was surprised when Sans made it to the kitchen, after all. 

Meanwhile, Sans was fine with him not asking. Eventually, he started to doze again, still tired from the long day. He leaned against the table with his arms folded and his head buried in them before Papyrus urged him to get back to bed. Sans groaned in protest, but he eventually dragged himself back to the couch amongst the pile of blankets and Undyne, who remained a loud, snoring pile of limbs.

It was morning when Sans woke again, bleary-eyed and hazy. He didn’t dream again and only vaguely remembered what he and Papyrus had discussed in the middle of the night. Undyne was awake and had even managed to make a pot of coffee without starting any fires. That was awfully kind of her.

She leaned against the wall next to the television, watching as Sans pushed himself up and looked around, trying to locate his brother. Papyrus would’ve prevented him from oversleeping.

“Pap’s on patrol. Just you and me, so,” she started, her tone peppy and with an accompanying smarmy grin as she swirled the contents of her mug. “Grillby, huh? How’d the date go?”

Sans was at least awake enough to conceal the irritation he felt at the enquiry, but not enough to stifle the flush that it brought to his face. It wasn’t as though he could control it anyway.

“fine,” he answered simply.

“Aww, C’MON! A date that was  _ fine _ was a bad date!”

Sans shrunk back against the back of the couch and grimaced when an errant spring nicked at his spine. He jerked forward and rubbed at the spot, then stretched a little to sort out the various kinks in his joints.

“hey, i finished those books alph lent me, so-”

“DAMN IT!” Undyne sighed with exasperation, then lurched herself off the wall and chugged back the rest of her coffee. Then she hauled herself beside Sans. She pointed a finger directly in his face, still holding the empty mug. “I’m IGNORING your pitiful attempt at a subject change! It’s time for YOU to come clean, bony boy!”

Sans made a grab for some more blankets to wrap himself in and over his skull. Undyne backed off a bit and lounged at the opposite side of the couch from him, eye blazing.

“the date went good,” he said quietly, not knowing why he had to tell her. “just really…  _ really _ great.” With the words, Sans was unable to resist the sheepish grin that tugged at his teeth and tried to suppress a laugh. “i just thought it got a bit… hot to handle.”

_ “Ohhhh?” _ Ok, that might’ve been the wrong thing to say considering who he was talking to. Sans pulled the blanket over his eyes so he couldn’t see the ludicrously toothy grin leering at him from the other side of the couch. “Why are you being such a shy DORK about this!? Did you two even KISS yet?”

Sans whipped the blankets off from over his skull and regarded Undyne with a bit of a glare, a spike of energy burning up in his agitated state.

“If you ask ME, I say you go over to Grillby’s right now and suplex him onto a table!” Her voluminous voice boomed so loudly that Sans was concerned that the people in the library down the street would hear. He also grew deathly silent over the implications, but she continued, “Give him a big ol’ smoocheroo! Tackle him to the floor and make your feelings abundantly clear! Then barrel on through to MAKE OUT CITY!! At least, that’s what I’d say if Papyrus didn’t ask me to watch over ya today.”

“oh, is that all that’s keeping you,” the skeleton groused, rubbing irritably at his skull. The mental imagery conjured by such a proposition made his mind reel, and Sans could only try to make a conscious effort  _ not _ to immediately react to Undyne’s words. So far, it was working.

“It’s going to be BORING.” The fish lady drawled as she stretched back against the couch cushion. “Sans needs a bath, Sans needs to do this, Sans needs to do that, make sure he does this…” She groaned, the noise loud enough to carry throughout the house.

Irritably, Sans flinched at the words. She backed off a little when she recognised his agitation, her single eye flicking to his sweater then back to his face. It appeared that she noticed something but Sans was more than willing to pretend that it didn’t happen.

Bathtime then, he lamented internally. Sans pushed himself off the couch, lurched to his feet and kicked away his shoes on the way upstairs. His socks came off next and he left them where they dropped down the hall to the bathroom. He let the tub fill before he closed the door and got undressed, yawning the entire time.

It was far too early to be awake. The thought lingered as Sans reluctantly sank into the tub until he was submersed clear to his jaw. Maybe he could stay in here to escape Undyne and just think about the date. Or maybe the next one…

It turned out that the resident fish lady had other plans. Her knock was as loud as her voice and very nearly jolted Sans clear out of the tub. Sans’ irritability skyrocketed again with her announcement; “QUIZ TIME!”

“does it really have to be  _ now?” _

Undyne ignored his protest. “OK! First things first: name the three constituents of the soul!”

Sans groaned, sinking further into the tub. His voice reverberated over the water, adding an echo to it, “love, compassion, hope.”

“Well that one was so easy a BABY could answer it!” Then she made a drawled out noise as though she was thinking. Sans speculated she was less prepared for the quiz than Papyrus would have been. “Ok, speakin’ of babies, how about this? Practical HP values for an infant are in what range?”

Immediately, Sans scowled at the door. “usually, between 10 and 20.” His was lower; much lower. He was getting agitated again. Idly, he rubbed at his right arm. “higher if they’re boss lineage.”

“Two points!” Sans groused at that. Just great. Another score to keep track of. “On cyclical nature: aggression in monsters starts at what stage?”

“which species.”

“Ohhhh. Tough guy. Alright, alright… uh, let’s say-” She paused to think about it. “Hotland crowd.”

Sans narrowed his eyes in suspicion at that. He wasn’t sure if it would be obvious of him to point out what she was doing, or if he should pretend it didn’t happen. As usual.

“pinstripe.” It didn’t vary too much between areas, but each culture had its differences. 

“Uh-huh. Uh-huh. And what does that mean?”

“goddammit,” Sans whispered, his voice echoing in the water. He slid down a little more. “last stripe before adulthood,” he called out louder, just a little warbling.

It went back and forth like that for some time, effectively trapping Sans in the bathroom until he realised that he hadn’t brought any other clothes in with him. He certainly didn’t want to wear his brother’s clothing again, so he sat up in the tub. His magic was arcing around him, made irate by the pop quiz, and Sans had been battling the overwhelming need to vent out the excess energy the entire time.

He didn’t want a repeat of the previous day, so he decided against any shortcuts. He coughed quietly to catch Undyne’s attention on the other side of the door. She laughed when he asked for clothes, then simply walked off. Hopefully she wouldn’t go into Papyrus’ room. He’d have a fit.

With water all over the floor after towelling off, Sans hid behind the door when it opened a crack. “Don’t worry. I don’t WANT to see your bony ass!” she called in, waving clothes that looked like his own. Sans grabbed them from her flailing grip and promptly closed the door to change.

Undyne had selected a dark blue tee that had the abbreviated elements ‘barium’, ‘cobalt’, and ‘nitrogen’ on the front and a pair of black snap-side track pants. Apparently Undyne didn’t get the memo that he didn’t have skin and had been a great deal younger when he last wore the pants in particular. Shrugging, Sans ditched his towel in the sink and opened the door.

“HA! Much better!”

Sans plucked at the shirt. “how far into my drawers did you have to dig to unearth this thing?”

“I dunno, I just grabbed whatever.” She shook her head with a grin, then seemed to notice something again. Sans avoided her look and attempted to walk past her.

Instead of managing that, Undyne grabbed the front of his shirt and dragged him back to study him. He lifted his hands placatingly, unsure of her intentions. Her eye wasn’t focused on his face, but a little lower.

“Oh. My. GOD!” She let go and Sans frowned in confusion. She giggled quietly at first, then broke out into a fit of howling laughter.

“jeez. rude.”

Several moments passed before she recovered enough to point to him, slapping her leg with her other hand and shaking her head. “He MARKED you?”

_ Shit. _

Sans clapped a hand over the spot, but it was already too late. He hadn’t checked the mirror. In fact, it didn’t occur to him that any of Grillby’s affections would’ve left any marks. He remained quiet and glowered at her.

“Oh my god, that is… too cute! FIRE HICKIES!! Date number one and he’s all OVER you?” Sans swatted her hand away when she reached to see better, his magic flickering aggressively. “Did I piss you off? Shit, I’m sorry-” She stopped laughing and blinked at the agitated stance; it was much different than being embarrassed over a little friendly teasing. “Hey, you ok?”

“you could say i’m twenty points into needing an outlet,” Sans grumbled, a vague reference to one of her quiz questions about aggression. He sighed quietly and attempted to calm down, pushing a hand to his face and pinching the bone between his eyes in frustration.

“GREAT! Then let’s spar!”

Uncomfortably, Sans shifted his weight from one foot to the other, but his magic flicked around him like a nervous cat’s tail. He swore softly; sparring with Undyne would probably dust him. She was hyperactive and pushed Papyrus to his limits, but his brother had a great deal more stamina than he ever would. Everyone did.

He stayed quiet but grew angrier the more he thought about it. He knew Undyne was waiting for an answer.

“i can’t,” he lied quickly. “pap said to chill.”

Undyne nodded her head suspiciously and folded her arms over her chest. “Well, in any case… What if I block, and just you attack?” She appeared to be pretending she hadn’t heard him.

“what?”

“I won’t attack.”

“that doesn’t seem like a thing i’ve ever heard you say. besides-”

Her eye and grin grew wider; “Hey! I’m trying to HELP!”

Sans grimaced. He attempted to shrug an apology just as Undyne grabbed him by the arm. Ultimately, to lead him downstairs and out the front door.

Sans remained defensive, led a little ways between Waterfall and Snowdin. It was strange to be outside without footwear or his hoodie, but for once the chill didn’t phase him. Undyne, meanwhile, had to run back inside for her coat, scarf and boots. When she returned, she continued to shiver in front of him, breaths huffing in the wintry air.

“the cold goes right through me,” Sans said deviously as he offered a grin and hid a select few stats from view. It was a little trick he’d learned on his and Papyrus’ first days in Snowdin, when some of the older kids were curious about the skeleton brothers.

She snorted in response and held out her arms. A hard line of blue-tinged magic sliced through the air as she summoned a spear and held it out in front of her. It was certainly a challenge.

“Ok, lay it on me! Hit me with all ya got!” She pounded her chest with a fist.

She seemed pumped to help, at least. Sans humoured her, conjuring a small feeble bone to flick at her as a test. It was quick and bounced off her head faster than she could move. She looked pretty upset about it, but eyed the attack in the snow to where it clattered to the ground.

“What the HELL was THAT?” She checked and her HP hadn’t even budged.

“you got a bone to pick with how i fight?”

“That was HORRIBLE! A WHIMSUN can hit harder than that??”

Evasively, Sans shrugged. He knew it was true, if said monster could even muster the courage to be around others. Even toddlers seemed more powerful in comparison, thanks to his stats taking a plunge after his accident. He had eventually learned not to care too much. It would’ve been enough to drive him nuts, otherwise.

Resigned, he sighed and raised his left hand to summon more attacks. Sans saw the way his partner grinned, as though Undyne anticipated a good exercise. That was a shame, considering he still felt so exhausted.

It had probably been not longer than half an hour or more before Undyne finally called it quits. She had drilled him to make smaller attacks, which peppered the snow around them like bony icicles before slowly dematerialising in their idle state. Sans was breathing hard, but not with as much difficulty as the night before, nor after his and Papyrus’ skirmish earlier that week.

He felt oddly better for it, if a little wobbly. She had taunted Sans about his damage output but he ended up chipping away five points from her by the end. After the first test attack, she was quicker to block. If anything, Sans had speed where his attack power lacked.

“I’m FREEZING,” she announced, dispelling her spear with a flash and rubbing at her arms against the chill. She hopped in place a couple of times, then stalked over to Sans in the snow, still catching his breath. “Ok, we need something to stuff our faces. Pap’s got food ready, right?”

Sans couldn’t help the shudder that passed through him at the mention of his brother’s food. Undyne unceremoniously tugged at his arm to pull him up from the snow and led him back to his house. She helped him brush the snow off his clothes and shoved him into the kitchen for something to eat. Then Sans reluctantly sat while she went about heating up two containers worth of spaghetti, humming idly to herself.

Then came the moment of truth. Sans stared at the steaming container in front of him while Undyne waited for her own to heat up. If he didn’t eat it… Undyne would tell his brother. And if he didn’t eat it, Papyrus would become upset that Sans wasn’t taking care of himself. His nonexistent gut twisted as he twirled a small portion onto his fork and brought it to his mouth.

For the most part it was sweet, but in a separate and completely unappetising way. Then salty,  _ way _ too salty, enough to make him choke. The oregano was overpowering and bitter to all his senses to the point where the noodles would have been a blessing if they hadn’t been drenched in garlic paste.

In a word, it was  _ disgusting. _

Wrestling with the flavour to try and absorb it, Sans stayed quiet but let his fork drop into the container. He didn’t feel well, before or after this. He couldn’t help it. His magic rejected it. Sans never thought it would be something that anyone without a stomach could do, but he made a retching noise and attempted to cover his mouth, abruptly turning from the table.

What little pasta Sans had absorbed came back up as tainted magic, effluvial cyan hue masking what the food once was over his hand. Undyne was at his side within seconds, ignoring the microwave chimes as she settled her hands on his trembling shoulders.

“Jeez! Maybe that sparring session was a bad idea,” she offered guiltily, her voice a register lower in worry. “Clearly you’re  _ really _ not feeling well.”

Once sure he wasn’t going to fall off the chair, she went to find a towel for him to clean up. Sans swore softly as she did, a twist of disgust in his magic threatening again as he half-leaned over the side of the chair, just in case.

“You should take it easy today,” Undyne suggested, her expression unsure. It seemed like she regretted pushing him. “You overexerted yourself yesterday and you’re still weak! So we’re gonna park our ass in front of the TV and watch it together!”

Unsure just why his body rejected the food but knowing that the taste had likely contributed, Sans only nodded, feeling worse than before.

After a couple of reality shows with Undyne bravely attempting Papyrus’ spaghetti, Sans drifted in and out of sleep thanks to the comfortable pillowfort they had surrounded themselves with. His body rejecting food had taken an entirely new toll on him and Sans felt more worn out than before.

Undyne had waited until he was in a deep sleep before looking him over. He was in rough shape and if she had known how exhausted Sans was, she wouldn’t have insisted on the sparring session. She felt guilty for that, but at the same time the guy always seemed to be hiding how he truly was feeling. While Papyrus’ cooking wasn’t…  _ great, _ it certainly wasn’t poison, so she assessed Sans’ reaction to overexertion.

For the most part, she updated Papyrus on how he was doing through texts and an uncommonly quiet phone call in the kitchen. Papyrus fretted on the other line so badly that she had to toy with him a bit; that Sans wouldn’t feel right if the Great Papyrus missed even one day of patrol on account of him, it being his dream and all. It seemed to do the trick, however temporary a fix it was. She sighed after ending the call.

After another hour of mindless variety prime time television, Undyne slipped off the edge of the couch and towards the door. As much as she hated MTT-TV, she left it on to keep her eye on Sans, who likely chose the channel to bother her. He hadn’t moved apart from a slight restlessness as he fell asleep, but he’d quickly settled soon after.

He would be ok, she thought, if she just left for a few minutes to get something she’d been aching to have since she got to Snowdin.

For someone so rambunctious, she could also be deadly silent. She pulled her boots on as she made sure that Sans remained asleep, then pulled on her warm jacket and scarf before leaving on tiptoes. It was a good thing the skeleton brothers both constantly harped on about not feeling the cold, otherwise she would have been worried about the draft waking Sans when she left.

She ended up at Grillby’s, grinning up at the warm neon sign of the restaurant before pushing the door. It looked like it was only half full with some chairs still turned over tables, but that was fine with her. Undyne’s plan had been to grab something to go from the start.

The heat was incredible compared to outside. It was cosy, warm, and the closer she got to the bar, the better it was. Red Bird turned from his story to the bartender as she approached, giving them her most winning smile.

“PLEASE tell me you have cheese fries!”

The bartender carefully rolled his shoulder, his fire looking a little dimmer than when she had seen him last. Maybe he wasn’t feeling well? It seemed like a lot of that was going around lately, she thought.

He remained silent as always, but gestured to a menu board behind the bar next to the shelves of liquor:  _ ‘Limited service. Sorry for any inconvenience.’ _

“Oh wow,” Undyne remarked after reading the orange chalk scrawl. “Are you not feeling well either?”

The fire monster gestured in response -- or would have, but his left arm jerked and he stopped short. He released a soft rasp of a noise and rubbed the arm as though in pain.

“Grills’ fishin’ with the other hand today,” Red supplied easily. Grillby turned his head to the bird and seemed to glower as though irritated by his translation. His flames flickered hotter and even crackled loudly. Red gave a sigh of resignation and leaned one wing over the bar. “Fine. He said ‘either?’”

“What?” It occurred to Undyne a little too late that Grillby had been the date, and what she said would have worried the mass of living fire. “Don’t worry about it! Sans is just cranky and overworked, hah!”

Grillby attempted to sign again, but couldn’t form half the words with only one hand;  _ ‘…my fault… he… out… protect me.’ _

“I’d say if he heard you were thinking that way, it would kind of upset him, y’know? The guy’s got pride and obviously cares about you. If he exhausted himself, it’s because HE wanted YOU to be safe!” Undyne shrugged uncomfortably. “I think he’d be MORE upset if he found out you’re trying to work through the pain instead of taking it easy!”

The fire monster seemed to consider it for a moment, then signed again.  _ ‘…arm… fire. Nothing to-’ _ He flinched when he automatically attempted to use his left hand and sighed in frustration.

_ “………Worry about.” _

His voice was quiet, barely a whisper and a crackling hum of fire so rarely heard by the patrons that Undyne had to lean forward to hear him.

She grinned knowingly at him. “Especially if you can’t communicate as well as you’d like, you shouldn’t force yourself.” Undyne sighed and idly scratched above the gills under her scarf, leaning back. It would smell less like sushi and more like shioyaki if she stayed any closer. “Take the day off, Grillby!”

The bartender gestured towards the floor with his good hand; many people were still eating and someone had just entered. Her gills flared as Grillby made a move to take their order, but she slammed her fists down on the marble counter, threatening to make it crack. He stopped, watching her warily in silence.

Undyne turned, still grinning. The entire patronage stared at her in abrupt shock, some even paused with food half-raised to their mouths. “Listen up, guys! Shop’s closed! Pack up and go! Get the HELL OUTTA HERE!!” Red slunk away from her craziness, sending an apologetic look to the bartender. “CAPTAIN’S ORDERS!”

_ “………Not necessary,” _ Grillby protested, stock still and sounding aghast.

“I’m MAKING it necessary!! And it’s my business that you recover in good health, which means NO WORK, PUNK!” Undyne ordered, shoving a finger in the fire monster’s direction.

Then she whirled around with a battle cry and set about telling what little clientele was left to hit the road. To prove her point, she wielded a stool over her head threateningly. The restaurant cleared out pretty quickly through the confused commotion.

**Notes for the Chapter:**

> Sans is around the equivalent of ~15 years in the flashback dream, still a kid. Meanwhile, Undyne is having major regrets about pushing Sans into that little sparring session.


	11. Chapter 11

**Summary for the Chapter:**

> Sans is instructed on how to access his reserves by Undyne, and breaks into Grillby’s when his friend doesn’t answer his phone.

When Undyne returned, Sans was asleep at the opposite side of the couch, but he had acquired a bowl of cereal that had spilled onto the floor. After a brief inspection of the area, she didn’t find any evidence that he’d been ill again, so she cleaned it up and went about passing the time on her phone until Papyrus came home.

He made sure to stay quiet, but frowned in concern when he saw Sans balled up in the same area as the previous evening. Undyne nodded at Papyrus, half in greeting and in reassurance. At least Sans had changed clothes, which meant his brother felt well enough to get up and do something.

Undyne took him into the kitchen and kept her voice low. “It’s like he doesn’t know what to DO?” she started, sounding appalled. “I don’t want you to freak out, but we sparred a little. HEY! I’m being HONEST here with you. Don’t worry, it was just a little test.”

Papyrus was hushed by her hand. She had quite literally grabbed his mandible to stop him from talking. He shot her a distressed look and she made a shushing noise.

“I dunno what’s going on with him, but it looks like he has all this pent up energy and he… doesn’t know how to FOCUS it?” Papyrus gave her a hesitant nod, still silenced as Undyne figured out things as she spoke. “It’s like he’s a kid, but… that’s just WEIRD.”

She unhooked her fingers from Papyrus’ jaw, humming to herself in thought as she leaned against the kitchen table.

“At any rate,” she continued, keeping her voice down to a harsh whisper, “I got some kids back home that struggle with this kind of thing? It’s actually pretty common, just… not so late. I’ll take a day tomorrow and help him through it. Gah, it’s like he WANTS to make us worry.”

“WILL… Will he be alright?” Papyrus adjusted himself, fidgeting worryingly.

She shot him a big grin and he tried his best to return a smile. He looked even more concerned, so Undyne threw her arm around his shoulders and gave him a noogie. “Your weenie brother’s gonna be just FINE, Papyrus!”

She spent the night again and woke shortly after Papyrus, who had taken it upon himself to catch up on some housework while she set about making another pot of coffee. The vacuum cleaner blared noisily and she glared at it as she yawned, mug in hand. Sans didn’t budge from his side of the couch at the noise, but he grunted in protest when Undyne gave him a small nudge with the tip of her boot as gently as she was able to.

Groggily, Sans rubbed at an eye with the heel of his palm. He felt marginally better. Not great, but it was a start. He yawned and pushed himself up to a sitting position, watching with detached focus as Papyrus vacuumed up his food attempt from the previous evening.

“TODAY, LAZYBONES, UNDYNE IS GOING TO BE YOUR MENTOR.”

Sans laughed quietly at that. “what?”

Papyrus finished vacuuming up around the couch before he bothered to continue, all while Sans gave him his most perplexed look and Undyne patiently sipped her coffee. Belatedly, Sans realised this was going to be the real deal. She was dressed warmly and already had her boots on. She also held onto his hoodie in her free arm for when Sans decided to get up.

“I HAVE UTMOST FAITH IN YOU THAT YOU WILL HAVE A SUCCESS!” Papyrus proclaimed. He didn’t allow for Sans to object as he strutted towards the door to pull on his boots. Sans made a move to lurch up from the couch, but Undyne kicked up her foot on him and it kept him down. “I’M GOING ON PATROL, SANS! I HAVE NO DOUBT AT ALL THAT UNDYNE IS BEST SUITED FOR YOUR TUTELAGE. HAVE FUN!”

Sans flinched when the door slammed, confused to the point of feeling mildly upset. It was entirely too early for this.

“are you  _ serious??” _

“Boy, is he EVER!” Undyne laughed, her teeth showing off in a grin to the point of lunacy. “He was VERY adamant!”

Sans groaned and pressed his face into his hands. “he’s getting back at me.” He shook his head and sighed in resignation. “fine. whatever. what do you got planned..?”

Undyne took another sip of coffee, then paused, looking down at him. Her brow arched sardonically and she leaned over him, barely putting any weight behind her foot, though it was enough to keep Sans pinned in place. “Get your jacket on, bony boy,” she leered ominously, holding out his hoodie. “We’re takin’ a walk!”

When he grumbled about breakfast, Undyne fixed him a bowl of colourful cereal and impatiently waited for him to eat it. It was easier done than the previous day, but Sans proceeded with caution. He ended up not eating very much of it, but at least it was sweet and it went down easy. He tried to take his time to wake up as he ate, but Undyne wasn’t having it. He wanted to wear his slippers and grew quite agitated when she insisted on his sneakers.

If there was any need for an outlet,  _ now _ was the time.

Instead, she led Sans outside to a spot near Grillby’s. They were just in front of the crossroads where there was a lot of room, but they were out of the way of foot traffic.

Distracted, Sans eyed a white sign on the door of the bar, then noticed that the bar’s shutters were closed. His brow furrowed as he pushed past Undyne, ignoring her preamble about her plans for him, followed immediately by a sudden protest.

“HEY! Hold up!” she called after him indignantly.

Sans scowled at the sign on the door;  _ ‘Premises closed by local authorities until further notice.’ _

He sent an accusing look Undyne’s way, silently demanding an answer. Undyne provided no explanation but she grabbed his shoulder and shoved him back to their training area, the opposite side of Grillby’s. She then rather forcibly pushed him down so his knees buckled. Sans ended up on his back in the snow, shooting her a sharp curse and a scowl.

“do you mind explaining what the hell you’re doing?”

She said nothing, but to her credit Undyne looked as though she was holding something back rather fiercely. She flopped down in front of him, long limbs akimbo before she drew herself up and cleared her throat.

“You fucked up.”

Sans pushed himself onto his elbows and glared at her. “what?”

She leaned forward so she could articulate every word with gruelling volume. “YOU SCREWED UP, FUNNY MAN!!”

Sans nearly barreled over and noticed how the kids running around nearby veered off-course into the opposite direction of them. He shrunk down into his hood and stayed quiet. She watched him, her yellow eye gleaming as she took in every single tell of his body language. Then she exhaled long and hard, as though she had finally come to terms with how aggravating dealing with Sans truly was.

Pulling Sans forward by one arm, he grimaced, on guard now. If Undyne was anything like she was with Papyrus, he was willing to bet she’d be yelling ‘snow-wrestling’ at any moment and he’d have to get his spine readjusted at the very least.

But it didn’t happen, which made it all the more peculiar. She sighed again, leaning an elbow against one crossed knee and stared at him. “Let’s skip the lecture, ok? I know what’s up.”

Sans stayed silent, his body tuned to either fight-or-flight instincts as his magic arced in defensive waves.

“We don’t have to put a name to it. Just know I’m here to help, ok? I deal with this kind of stuff… pretty consistently. And you’re being a huge baby about it. I’m gonna need you to knock it off.”

“i don’t-” Sans stopped himself short, his mind racing to and fro. Did Undyne know about the whole delayed puberty ordeal, or was she merely concerned for him? Admittedly, it was difficult to tell.

To her credit, Undyne waited a few moments more for Sans to continue before pressing on. “I’m not insinuating anything. Hell, I don’t even WANT to know? I just know that your brother worried about you all last night and the night before. You HAVE to start taking better care of yourself!”

“so that’s what you dragged me out into the snow for. thanks, chief. it’s really lifting my spirits.”

“Don’t be cute.” She grabbed a fistful of snow; it was light, powdery and barely packed at all. In fact, it would be perfect for her exercise. “As a sentry, you’re smart and can get around quickly, but you’re USELESS when it comes to actual fighting. I figured it out during our sparring session yesterday. Instead of using your reserves like any regular person would, you’ve gotten into the habit of pushing yourself. It’s stupid and DANGEROUS!”

Sans remained silent. He slouched in feigned disinterest, idly drawing a line in the snow with a bony digit. His magic coursed harsher with his anger at the truth, though.

“And as a result, you’re cranky like a teenager and have SCORES to blow through, but you’re not. Doing. SHIT.” Her gills flared with his noncommittal shrug. “Ok, so to my point-” Undyne continued almost sweetly, her wide grin betraying her tone, “-is that. You need. To ACCESS it. Which is why we’re sitting in the goddamn freezing snow. So I would APPRECIATE IT, if you at least TRIED?”

Sans sighed, one eye open while the other remained closed in disinterest. She had a point, though the more she pressed it, the more hassle he felt it would be.

Unfortunately, she barrelled on. Undyne scooped up a pile of snow in front of them and gestured to it. Her explanation dealt with how normally she used seeds or spores in Waterfall, but snowflakes would work just the same. He would filter his energy to move the tiny flecks with his magic to create a separate pile.

It was infantile and degrading. Sans wanted nothing more than to walk away and not have to deal with anything at that moment. Sure, she was trying to help, but he wanted to escape. When Sans moved in a way to suggest that he intended to get up, she reached over the small pile between them, her expression pleading as her hand rested on his shoulder. It threw Sans off, his eyes widened slightly as though he didn’t know what to expect next.

“Please. For Papyrus and everyone you care about. AND yourself.” He flinched. That was low. It took several moments for Sans to resettle, then slowly nodded his head in silent agreement.

Most of the morning was spent in practise, with Undyne giving instructions and Sans making attempts. He earned a few light smacks that thankfully didn’t hurt when he automatically drew from his stamina.

Switching between the two forces was something he had to get used to, now that he had learned that there was a difference. Deep in his soul, there seemed to be an unlimited font, replenished while he slept, itching to get loose… Sans just had the habit of drawing from his stamina first.

_ There’s a reason for that. _

He blinked to clear away the intrusive thought. However mundane and trivial it seemed, Sans moved the snow, flake by tiny snowflake, from one side between them to the other. Admittedly, it was more difficult than he had initially thought and just as tedious. 

Pretty soon it was easier to adjust to, but the effort of switching last moment to his reserves was exhausting him. Once or twice, Sans simply propped up his skull on his right hand while his other raised between them, poised with a larger clump of snowflakes surrounded in his cyan hue. He ended up nearly falling asleep that way, his magic holding onto it midair.

“Hey, blue boy!” Undyne snapped, then clapped her hands in front of his face to wake him. When Sans opened his eyes again, it was to Undyne shivering violently in front of him. The pile was larger on the right than on the left. He’d made progress. “I th-think y-you got it-t!!”

“oh. huh.” Sans eyed his left hand, then glanced to Undyne, who was trying her damnedest to keep warm. “you’re kinda…”

“D-DON’T?”

“…flash-frozen, heh.”

“M-makin’ him close up really b-bit me in the ass.” She sighed and got up, her body trembling. “C-could REALLY use the heat! Y-your stupid house isn’t c-cold, but it’s n-not warm EITHER!”

Sans got up and brushed himself off. He wasn’t entirely bothered by the cold, but he looked up to the second floor of Grillby’s building like he could imagine the fire monster looking down at them. He wasn’t in any of the windows, though.

“ok… but why did you?”

“F-freakin’… he was t-trying to wo-work with a b-bum hand!” Undyne shot back irritably, then abruptly sneezed. Sans stared at her as she encircled her arms around herself to try and keep warm. “I-I told him, h-he better get b-better soon! H-he couldn’t eve… even S-SIGN, it was so b-bad!!”

Sans looked up again and walked around to the front of the restaurant. It was easier to see the dim light upstairs, and after watching the muted glow for a moment, Sans fished his phone out of his pocket and quickly scrolled down his contact list.

“What’re you d-doing?”

Sans raised a single digit to his teeth while he was on the phone, waiting for the other end to pick up. His soul hammered hard with worry and Sans paced around outside of the bar, impatiently waiting.

There was an empty click as the call disconnected. Grillby didn’t answer, nor did he have voicemail. Confused and mildly alarmed, Sans stared at his phone, then promptly approached the door and started to beat on it with his fist.

“WHOA! E-easy, Sans! He’s f-fine, he-”

He ignored her, instead trying the door, but it was locked. Sans clenched his teeth to bite back the gnawing worry. He stopped knocking and stepped backwards into the street so he could look up at the window again. He could still see the fire monster’s glow upstairs, but it hadn’t moved.

Immediately, Sans quickly tapped out a message and sent it.

Grillby (Last message sent: 9:24am);

*im comin up

“go back to our place and get warm,” Sans told Undyne as he stalked away towards the opposite side of the bar. “i’ll be back later.”

As he made his way towards the rear of the building, Sans heard her footsteps behind him and a huffed protest, but he had already drawn on his reserves to take a quick shortcut. He was several feet away from Undyne by the time she thought to follow, and when he rounded the corner, Sans immediately warped into the dark bar.

He heard a startled exclamation from outside, along with a few choice swears and his name amongst them. Sans waited in silence for Undyne to give up her search, his breath shaking as he tried to remain calm. While he had stayed behind at Grillby’s quite a few times overnight in the past, he’d never been upstairs. It didn’t take a genius to figure that’s where the fire monster’s suite was.

The large room was cooler and held no trace of the resident fire monster’s ambient heat. Sans slowly walked towards the back of the bar, the light of his magic’s hue guiding the way. All the while, Sans tried to keep a handle on his nerves, checking his phone as he rounded the corner of the kitchen to explore.

“hey, grillbz..?” Sans cautiously called out. His voice sounded oddly thick with trepidation with no one else to hear it but himself. The fire monster didn’t respond from the darkness, so he pressed onwards. He tried to phone again, but the call disconnected once more. 

Grillby’s seemed like an entirely different place now that it was empty. It brought up a sick, wretchedly lonely and fearful malaise in Sans’ soul the further he walked into the pitch. Idly, he grasped the fabric in his pocket and habitually checked his phone, just in case he missed a message.

He hadn’t.

“this isn’t funny, man…”

The stone oven in the kitchen hadn’t even been lit that day and remained cool. Everything looked in disarray. Dirty pans, pots and dishes were stacked to one side of the counter and half-dished plates of food had been left out to dematerialise with age. Sans sucked in a calming breath, his entire being dreading the chill of  _ ‘what if?’ _

“…grillbz?” he called out again, a little louder.

Eventually Sans found a flight of stone stairs leading up and he drew in shuddering breaths to calm himself. At the top he could see light, though it was dim. His bony fingers trailed up the iron bannister, lightly grating as he crept over the worn steps.

At the top of the stairs, it opened into a wide corridor with the walls covered in shelves laden with books and odd peripherals that he didn’t care to look at. Light from the room beyond spilled out into the hall and Sans’ soul suddenly shuddered with apprehension. What if Grillby was more seriously injured than he had let on..?

Sans pushed away the intrusive thought and started towards the end of the hall, grinding his teeth to stop himself from panicking. The door was ajar only a little bit. Carefully, Sans knocked twice, hopeful for an answer.

There was none.

Sans drew in another breath, trying to calm his nerves until he had the courage to push the door inwards. It creaked softly in the silence of the room. It felt wrong not to hear any crackle of flame from beyond, but at least there was still light coming from the bed.

“…grillby?” Sans’ voice was hushed now, unsure.

A fiery form lay on the bed with flames so low Sans could make out every detail of Grillby’s body. He wore a plain, loose button down grey shirt and black shorts, sprawled on his bed with very little blankets. His entire form was glowing, but there was only a wisp or two of actual fire that Sans could see. Grillby’s left arm was bare and was blemished up to the elbow, embers quietly floating off his hand.

God, Sans hoped that he was only sleeping.

Suddenly Sans was extremely doubtful of what he could do to help. He crept closer still, taking care to be quiet in case he would startle the sleeping fire monster. To break the tense silence, a soft jingling tone came from the desk to Sans’ right, where he could see Grillby’s phone light up with a reminder. Sans recognised his own message when he peeked at it, labelled ‘Funny Bone’.

Sans exhaled through his nasal cavity, unable to help the soft laugh at the bad nickname. Behind him, Grillby shifted on the bed with a soft raspy noise, brightening the room by a bare fraction. When Sans turned back to check, Grillby had hung his right forearm over his eyes with a deep sigh, then seemed to settle again.

Sans drew nearer, fidgeting with a loose thread in his pocket as he searched Grillby for any sign of pain. The embers that floated off the fire monster’s injured hand and arm drifted away, only to snuff out in the blink of an eye. Grillby didn’t appear to be in any agony, but the boards beneath where his arm hung off the side of the bed were scorched as fire trickled down like molten liquid and dripped to the floor.

As he was able to get closer without disturbing him, Sans knelt beside the bed, taking in the sight with growing unease. Even when he recalled Grillby sleeping at the resort on their way through to New Home, Sans had never seen his flames so low. 

With his torso exposed, Sans couldn’t help the pang of guilt when he saw similar burns as Grillby’s injured arm. They were faded but still visible, a line of darker fiery mass like a scar from when he carried Sans through the rest of Waterfall. There had to be deep pools Grillby had to cross, marking him up in order to reach the heights on Grillby’s body. Anger flared in Sans’ soul, twisting and ugly blame thrown at himself for being so weak.

Sans would make it up to him this time, at least. It wouldn’t be enough, not after all Grillby had done for him, but there was little sense in Grillby suffering if Sans could heal him. Now that he could kind of manage his reserves, Sans would try. He drew in a soft breath, Grillby’s gentle warmth catching over his teeth as he cautiously reached out to cradle Grillby’s injured left hand with both of his own.

Grillby’s fingers twitched slightly. Sans stayed completely still, watching Grillby’s form as he drew in his reserves to go about healing. The cyan magic from Sans’ fingers mingled with Grillby’s dark orange form, turning it an icy green. Then, strengthening, it brightened a little more to the familiar healing glow.

Grillby shifted as another sleepy sigh escaped him.  _ “…Sans?” _

Sans offered him a grin, though he quickly realised that the fire monster probably couldn’t see him without his glasses. It didn’t seem as important to be quiet or as careful now that Grillby was awake, so Sans pulsed more magic to heal with a soft chuckle.

“how’d you figure?”

Grillby turned his head slightly and rubbed over his visage with his free hand. As he shifted on the bed, his fire and heat kicked up a little like a small campfire starting up. Sans watched in curiosity as new flames kindled, obscuring the mystery of Grillby’s body and the vague little fissures, barbs and crags that covered it.

_ “…Heat sink. And who else would have the audacity to break into my restaurant?” _

Sans adjusted his grip on the fire monster, moving his left hand to cover the water burn on Grillby’s forearm to heal it next. The odd weeping flames had disappeared over time, but small hairline cracks still managed to glow brightly against orange and red.

“heard you were ordered to keep your hands to yourself. aren’t you supposed to tell your neighbours about that kinda thing?”

Grillby uncovered his face to look at the window by the bed, then turned to face Sans.  _ “What time is it..?” _ His voice crackled thickly with sleep; Sans told him and he seemed to groan in protest.  _ “…Too early…” _

“i think i’m rubbin’ off on ya, grillbz.” Sans couldn’t help but chuckle. Grillby must’ve been thinking of something else, since another warm flare-up caught Sans’ eye. Below friendly fires, it looked like Grillby was attempting not to smirk. “what’s the joke?”

Dismissively, Grillby merely shook his head and pushed himself up a little so he could grab his glasses from the nearby nightstand. He fiddled with them for a moment before he put them on and drew in a deep breath, eyeing Sans wearily.

_ “Don’t feel obligated,” _ he said after a few moments, watching as the coil of unstable magic wafted from Sans’ bony fingers.

It mingled with his fire and sunk into his arm with a subtle ache, interfering with his natural temperature. Grillby’s fingers twitched again at the gentlest of touches, healing the searing injury to a dull throb. Grillby couldn’t repress a grimace as the tingling and heat-void became too much. Gingerly, he pulled his hand away.

“i want to.”

Even as he protested, Sans relented and rested back on his legs with a soft huff. Papyrus had been right; healing took a lot of stamina, but he was sure he could do more. With Grillby watching him, Sans felt as though he probably shouldn’t push his luck.

The bright crack of Grillby’s smile quirked. Slowly, like he might spook Sans if he moved too quickly, Grillby gestured for him to come closer. Once Sans approached the side of the bed, Grillby put his arm over Sans’ shoulder and guided him even nearer, his hand settling at the back of Sans’ neck.

_ “…Look exhausted.” _

Sans leaned forward a little more, urged by the gentle caressing just below the back of his skull. “i could nap,” he murmured with a soft sigh. He would’ve shrugged but Grillby’s hand slipped under his hoodie and shirt, lightly rubbing at his spine.

It was tender and devine. Sans melted into the chaste touch, folding both of his arms over the side of the mattress to lay his head down on top of it. Despite himself, Sans’ eyes almost drifted closed through the attention.

Grillby leaned forward and kissed his brow, the warmth meeting from the back of Sans’ skull to the front, completely flooding him in pillowy-soft comfort. Sans hummed contentedly even as Grillby’s hand stilled and then slid back up to his shoulder.

_ “There’s room for one more.” _ The invitation was bold, so much that Grillby thought with Sans’ pause that it had been  _ too _ brazen. He relished the thought of being close, especially if Sans was so willing.

Sans laughed, his soul nervous and fluttering. He didn’t mind the offer, even bravely moved to kick off his shoes at the invitation. Soon his hoodie joined them on the floor and Grillby had his arms wrapped around him, as close and as comfortable as Sans had ever felt in his entire existence. Grillby sighed contentedly as he shifted closer, his flames moving languidly in a restrained effort not to fully explore now that their point of interest was so near.

It was safe, it was warm, and Sans felt more cherished than he could ever remember being. His left arm was curled between them while his other hooked under and around Grillby’s right arm, pulling him close.

He inched his face towards the fire monster’s, taking a moment to just look into his eyes. Sans couldn’t help a bashful laugh, rubbing his hand along the back of the fire monster’s shoulder. Grillby couldn’t help his sleepy smile, curling against Sans’ touch and radiating dense heat.

“i’ll keep going after the nap,” Sans decided as Grillby rested his chin against the top of his skull. He felt Grillby’s hand rub against his bones through his clothes and sighed contently, his fingers idly grabbing at Grillby’s shirt. He then jerked suddenly with a startled yelp when Grillby’s hand found his lower spine and gently flicked it.

_ “When you learn to stop being so… jumpy…” _ Grillby chuckled, giving the column of bone a soft pat. Sans resettled, but he was unable to still the trembling to his satisfaction. Not with Grillby’s hand lingering there in direct contact with bone.

There was a lighter pique to his flames then, as Sans’ reaction had been more intense than he had anticipated.  _ “…Perhaps.” _

Sans was only paying half attention to the words, focused on the gradual heat that seeped into his spine in both directions. He turned slightly, tilting his head up as he moved his free hand to uncover Grillby’s throat of fabric and replace it with his mouth. He felt Grillby shift in turn, then heard a low chuckle when he conjured his tongue and pushed it against the heat.

_ “What are you up to?” _

Sans huffed against his neck, the soft sizzling sound oddly ridiculous in the quiet room, but he was determined. “gotta mark you back,” he replied simply after pushing himself up to inspect the spot. There wasn’t anything there, and somehow Sans thought it unfair as the flames flickered at him tauntingly.

Grillby laughed in his throat at the prospect.  _ “One can certainly try.” _

“thanks,” Sans replied dryly, holding back a shudder in response to another wave of heat up his spine when he inched closer.

He pondered it for a moment, reasoning that maybe a wet tongue wouldn’t work after all. Sans almost seemed to frown at the idea, then another thought came to mind. Bolstered, he buried his grin at the base of Grillby’s throat and tried something a little different, replacing the wetness for something else.

A startled jolt passed through the fire monster’s body along with a shudder and a surprised gasp. Sans’ soul flickered in response and he shot up to look at Grillby. Just in case he’d done harm instead of… well, whatever he was aiming to do. Grillby took care to hide his surprise behind his fire, but the brightness of his eyes betrayed him. Sans offered him a wide grin then, watching as Grillby’s torso heaved and his fire danced with paler colours. Embers popped around them excitedly like sparklers.

“did that fire up anything?” Sans teased, unsure, then jolted again when Grillby gently tugged at his spine. He huffed softly when the warmth kicked up a little hotter. It didn’t feel unpleasant, just… unexpected.

_ “What was that..?” _

Sans gave a vague shrug, slightly distracted. “…cold?”

It had been experimental, pulling his magic to mimic Grillby’s heat, then sent it into the complete opposite direction. He watched as the fire monster’s breaths eventually calmed down. The reaction filled his body with something, and all Sans knew was that he wanted to try it again.

Hesitantly, Sans leaned down again to his throat and Grillby stilled in quiet anticipation. There hadn’t been a mark left behind yet, and when Sans’ conjured tongue touched his fire, Grillby’s body arched slightly against him.

Grillby’s right hand travelled up with a low noise in his throat, plucking every segment of bone until it hooked between Sans’ lowermost ribs. Abruptly, Sans stopped with a sharp inhale, his body shaking. The heated pressure felt as though the rib would snap.

“e-easy,” Sans murmured nervously, pushing his hand between them to create a slight distance. Carefully, he plied warm fingers from his rib cage and regrettably out from underneath his shirt. Sans ignored Grillby’s concerned look and instead held onto Grillby’s hand, inspecting his handiwork at the base of his throat. Meanwhile, the fire monster put that reaction to his touch away for future consideration.

“y’know… this isn’t fair,” Sans complained mildly. He traced his thumb against the area as flames gently licked at his fingers. It appeared that ‘cold’ didn’t do anything to mark Grillby’s body either, but it gave an interesting, pleasing reaction anyway.

Grillby watched him, staying still, but he closed his hand around Sans’ fingers and pulled him close.  _ “That is fine.” _ He shrugged slightly, like it was no big deal. He guided Sans down, and eventually Sans recognised the careful way he moved and leaned down to resume their previous position, curling up beside Grillby again.  _ “Far too early, anyway…” _ Hopefully, they would have plenty of time in the future for exploration.

Sans assumed that it was because he woke Grillby up and he still needed rest. So he merely nodded, hunkering down onto the mattress. Warm arms encircled Sans again after Grillby returned his glasses to the nightstand and Sans inched as close as he could possibly get. It was something else to listen to the flutter of flames peter lower as Grillby eventually fell back to sleep, and Sans would hold it in his memory forever.

It wasn’t long before Sans joined him, tuning out the faint hum of his phone buried in his jacket on the floor.

**Notes for the Chapter:**

> In canon, monsters are made of 'mostly magic', which I figure is like humans being made of 'mostly water'. Because of this whole monster genesis thing going on with Sans, he was unable to differentiate between stamina (bodily magic, we'll say) and reserves (actual magic). Sans sucks at healing because his stamina is so low, and because it's been so long, he automatically draws from what he's been using this whole time. Hence the sickness.
> 
> Hunger also plays a kind of vital part in Postcards throughout; when Sans has a buffer, he can go longer without food. But... the only good way to heal up after exhausting yourself is sleep, not eating when you don't have to. :( Poor Sans!
> 
> I think Undyne was very helpful in this chapter, and Sans breaking in is just... who does that?
> 
> ...hey look, they got a room. (*ﾉωﾉ)ｷｬｰ


	12. Chapter 12

**Summary for the Chapter:**

> Studying with your boyfriend really never stays as innocent as you intend it to be. Grillby gets a demonstration on how different the skeleton diagram differs from Sans.

Only a few hours had passed when Sans woke up again. It felt unreal curled up together like this, to be bathed in a gentle glow and warmth, wrapped loosely in Grillby’s arms. Sans didn’t immediately move, kept in that blissful in between world of waking and dreaming.

Blearily, he looked around as consciousness gradually returned to him. Grillby was still in deep slumber, the subtle shift of low flames curling against his form. He was more or less solid. Without those bright eyes on him, Sans was able to peek at every detail without worrying about it too much.

Small glowing fissures scored along the surface of Grillby’s body, the tiniest of crag-like formations trailing subtle changes of colour. In a way, they looked like the vibrant geodes embedded in the secluded quarries where Waterfall and Hotland met. They shifted and even seemed to disappear with every breath Grillby took, and the quiet flames circled around his body and under his clothes.

Sans wasn’t from Hotland. He had to wonder how the place never burned to the ground, but it had to be a fire monster thing. As if beckoned by the idle thought, a few flames stuttered around Grillby’s shoulder and down to Sans’ hand, moving across it. He watched it all rather calmly, feeling no threat as the gentle heat soothed his weary body. It gave Sans very little excuse to move of his own accord.

Still, Sans moved just enough to gently glide his hand down from Grillby’s shoulder to the small space between their chests. Grillby leaned closer in his sleep with a quiet sigh, but didn’t wake.

Sans couldn’t help the twitch of a smile that crossed his face with the impish thought that came to mind. As much as he liked being curled up next to the fire monster, he rather enjoyed Grillby’s company when he was awake. Lightly, he pressed his palm against Grillby’s chest, watching as the flames ran around his hand the more Sans gathered his magic there.

It only took a moment. A startled gasp came from Grillby and a puff of warm air grazed Sans’ temple as he gave the fire monster a mild but chilly pulse of harmless magic. Jolted out of sleep, Grillby blinked around in confusion as fire harried his visage. Sans flinched at the same time, but it wasn’t due to the resulting movement.

“mornin’,” he drawled sleepily, hiding a grimace that the magic usage brought on. It took a moment for the fire monster to gather his bearings, then lean closer. “i never took you for a late riser, g.”

The start of Grillby’s reply resembled the rasp of popped kindling, until they eventually formed coherent words;  _ “…arely have so many mandatory days off.” _ He rubbed at his face with one hand, then reached to the nightstand for his glasses with a soft grunt.

Soon Grillby was able to see the smaller monster curled beside him on the bed, but a frown touched his bright eyes. Sans appeared somehow more exhausted after the nap, he noted with concern.

“what’s that look for.”

Grillby made sure to conceal his expression carefully as not to raise further suspicion. Thanks to the small jolt of ‘cold’, his flames were kicked up and lively, the sensation confusing and foreign.

_ “Eaten yet today?” _

Sans didn’t answer, nor did he even shrug. Grillby pushed himself up to a sitting position, giving Sans’ shoulder a soft pat. Now that they were a little closer, he found little reason to withhold the ways he showed affection anymore. The sigh the fire monster exhaled was hot and harsh as he carefully manoeuvred around Sans, then snaked his bony arm under his own to pull Sans up.

“aww, grillbz… can’t i stay in bed?” It was mostly a joke, but Sans honestly felt like he could sleep for at least a couple hours more. He looked inwardly and couldn’t hide the grimace this time. He was down to two points. Wait, no; it had just rolled over to the last, his buffer gone despite all the rest he had.

Sans sighed in resignation; he didn’t have all that much food lately, he realised. “i guess i should eat, then.”

It took him a moment to get up. Feeling as weak as he truly was, Sans made a show of stretching so that he didn’t worry Grillby. The fire monster looked through his phone by his desk, obscuring his reactions with his flames, though he gave a pensive hum once or twice as he read over the messages.

Sans watched him for a moment as the last couple of clicks popped from his joints and Grillby tapped out a quick reply to whomever was on the other end. When he appeared finished, Sans pushed himself up and followed him into the next room when Grillby gestured for him to follow.

It was a little odd to see Grillby’s apartment. Unlike down in the restaurant, it seemed more like a place to house his belongings and to rest. The shelves that Sans didn’t care to look at on the way up were littered with a thin layer of ash. Old books, textiles, and small metal instruments were strewn about, and there was even a small globe that rotated on an axis when Sans gave it a test spin. For a monster composed of fire, Grillby certainly kept a lot of things in his suite that were flammable.

The next room was a kitchen smaller than the one downstairs, but it was just as messy. Sans had something of impressionistic whiplash as he leaned against the counter with several days’ worth of dishes, which Grillby didn’t even bother to excuse. Then, rather modestly, there was a flare of fire magic as Grillby held up a few dishes. Both hands engulfed in flames to incinerate any leftovers until the plates were clean before dusting off the ashes. Sans whistled, impressed, and Grillby only shook his head with a wry smirk.

_ “…Don’t normally entertain.” _ It was a rather poor excuse for being messy, Grillby thought, but there was only so much one could do about where ashes fell, being the primary cause for them. Keeping the areas upstairs wiped down always seemed pointless after hours keeping his restaurant clean.

Sans only laughed. “wow. if you saw my room…” His sock collection and dirty laundry would be enough to chase Grillby off for good. He saw the smirk it earned him at that, no matter how much Grillby tried to hide it.

He was made to sit on a high back iron-wrought chair while Grillby fired up something to eat. Sans watched him as he slouched in place and looked around, finding the most mundane items in the kitchen a little interesting.

“hey,” he started after a moment of watching the fire monster pull bins and a frying pan from one of the overhead cupboards. Sans noticed that Grillby seemed to be using his left hand just fine, even though it still looked blighted and sore. He offered a tired grin when Grillby turned to him expectantly. “…how’s the, uh…” Sans gestured with his own arm.

_ “…Would have rekindled,” _ the fire monster replied simply, continuing to bring out ingredients.  _ “It wasn’t really required.” _ At least, it certainly wasn’t if it exhausted Sans to his current state. Guilty, Grillby managed to hide it, though perhaps a little too well.

For some reason, it stung. Sans managed to shrug it off as though it didn’t bother him, but he didn’t press it. Perhaps it was premature. Grillby turned again once the counter was loaded up with what he wanted and leaned over the small island that separated them.

_ “…Though, it is very much appreciated.” _ Grillby watched as a subtle bloom of cyan peeked out from the dark collar of Sans’ shirt and gave him a reassuring smile. He liked the way Sans literally glowed with appreciation. Hanging onto the thought, he then turned away to start cooking.

Sans watched as he did, his eyes half-closed through a hunger daze. Silently, he hoped that he wouldn’t make a fool of himself again. He had managed to keep the cereal down, and bearing witness to how Grillby cooked was a treat in itself. He heated the frying pan with his magic, whipped eggs, milk, flour and sugar into a bowl before ladling it out into a sizzling pan. 

Sans folded his arms over the counter, his skull resting in them as he watched, enthralled, until the very last moment. It smelled heavenly as Grillby put the last finishing touches in front of him, two plates stacked with thick, fluffy, golden pancakes drenched with butter and syrup. To top it off, Grillby shook a light dusting of powdered sugar on them for good measure.

Impressed, Sans was all too eager to dig in. Grillby waited until the skeleton bit into his first helping, who then visibly relaxed in apparent bliss.

“why the hell you don’t do breakfast, i’ll never know.”

The fire monster rolled his shoulder as he leaned against the counter, still standing.  _ “No one comes in the morning.” _

“i did,” Sans protested, sticking another bite of pancake into his mouth with eager gusto. “fftwice.”

Grillby was able to catch his smirk in time for Sans to  _ just _ barely see it, his brow raised comically.

“no seriously, grillbz, if you’re holding out on some good jokes, you gotta share.”

Grillby only grinned to himself, refusing to give Sans the satisfaction of understanding the innermost workings of his mind just yet. He ate a little more of the brunch as Sans warily watched him. Grillby could literally see the cogs of his mind moving.

“throw me a bone, here.”

_ “You recall,” _ Grillby relented, his grin showing a bit more,  _ “when you suggested at the capital, that I wouldn’t mind you in bed?” _

He delighted in the way Sans snapped to attention, his eye sockets blown wide as his magic’s hues flooded his bones in vibrant intensities. The grip on Sans’ fork stilled midair between his plate and his mouth while Sans stared at Grillby. Then he tensed and slid down his chair a little, unable to meet Grillby’s gaze.

Such a bashful boy.

_ “…Might have mentioned something along those words even earlier than that,” _ Grillby added, unable to resist the tease.

He watched as Sans tried to grab over his shoulder, likely in an attempt to find his hood to hide. Such a shame his hoodie was in a crumpled heap on the floor of Grillby’s bedroom. Instead, Sans leaned against his hand, elbow on the counter, and portioned off another piece of pancake like the whole thing had never happened.

_ “Point being,” _ the fire monster continued, waiting for Sans to finish his mouthful,  _ “Such an event proved not to disappoint.” _

“o-ok,” came Sans’ go-to word. Grillby found that he said it when he didn’t know what else to say.

Though honestly, Grillby realised it was an obtuse way of saying that he enjoyed the added body next to him, that he even wanted it to happen again. Perhaps quoting Sans’ embarrassing slip-ups was inconsiderate, but the reaction was rewarding in its own way. It was also amusing, considering Sans’ earlier boldness in wanting to mark him. Everything was contradictory to Sans’ inexperience. Grillby couldn’t help his grin with the thought throughout the rest of their meal.

Now that his hunger was satiated, Sans followed Grillby back to the bedroom, bee-lining to his hoodie to grab his phone. Sans had heard its buzz even as they made their way from the kitchen, and he wasn’t looking forward to the maelstrom of messages that awaited him. 

There were several missed calls and over fifty messages from Undyne, Alphys and even a couple from Papyrus. To say the least, Undyne was unhappy that he had given her the slip. She figured out where Sans was pretty quickly, but told him to take it easy as she had to go back to Waterfall. Alphys was simply trying to get a hold of him for Undyne’s sake, and Papyrus was checking in on him, as usual.

He decided to only text back his brother for the moment.

The fire monster seated himself on the bed after checking his own phone. Sans looked up and said nothing, then heard a wistful sigh.

_ “The authorities mandate another sick day.” _

Sans glowered, directing it at his phone more than to what Grillby said. Undyne had mentioned something like that in a text, in between how he had failed miserably on his quiz and needed to study more. Sans hadn’t thought he did. Sure, a few questions were answered rhetorically and others with jokes, but he didn’t think he  _ failed. _

Idly, he idly wondered if he could get away with getting the reading material again and coming back.

“why don’t I keep you company today? maybe you could help me study…”

The offer surprised even himself, but Sans waited for the fire monster’s reaction. Grillby only nodded. Something about the way his fire moved made him look pleased.

Now that he was feeling better thanks to the amazing food and the nap for most of the morning, Sans pulled on his hoodie and shoes while the fire monster moved to clear a few wayward dishes from his bedroom. He followed Grillby downstairs and went to use the main entrance when the fire monster caught his arm.

_ “Fire exit,” _ his friend suggested, looking towards the back of the bar. Sans gave him a crooked grin, a joke forming in his mind as he let Grillby tug him closer.  _ “…Not made of fire, I know.” _

Sans blinked at Grillby. That had been exactly the joke he was thinking of, but he’d been beaten to the punch. Maybe Grillby was getting used to his puns already? Or maybe they had more in common than they thought. Sans decided to let the odd familiarity slide and chuckled lowly when Grillby opened the door for him.

He passed a few neighbours on the way. A couple asked how the date had gone, while another told him it was about time the two of them hooked up. Sans was flushed by the time he made it to the house, unable to think much apart from what went on during the date.

Distracted, Sans grabbed a few textbooks from his room and pushed them into his bag before strolling across the living room, tracking snow everywhere. On his way past, he paused beside the sock, grinning as he moved it a little, his brother’s fresh note telling him to bring it back to his room. He found a marker in the kitchen and returned to write “ok” on it, and then he left again.

He returned to Grillby’s, using the fire exit once more to gain entry. Sans met up with him upstairs again. It looked as though the fire monster had only moved to change into a pair of dark plaid pyjama bottoms, which was probably better than the shorts he’d been wearing before.

He looked far more awake than Sans last saw him and his light glowed ambiently around him as Grillby leaned over his desk, reading a ledger.

If Sans didn’t know better, he could’ve sworn Grillby looked perplexed about something. Or at the very least, if Sans was sure in his ability to decipher his expressions. Even though he was curious, it wasn’t his business. Grillby noticed that Sans had come back and turned to face him, closing the ledger as he did.

_ “All set?” _

Sans shrugged as he went back to the bed, once more discarding his hoodie next to it in an unceremonious heap along with his shoes. Apart from a desk that only had one chair, Grillby didn’t really have any other space to sit. It was cosy and did the job, at least. Negligibly, Sans upended the bag onto the mattress and sat next to the pile, glaring at it as Grillby took a seat across from him.

_ “Why the need for…” _ Grillby paused, taking  _ Magical Bodies & The Housed Soul _ from the top of the pile. Sans saw the way his flames lowered significantly around Grillby’s hand, careful not to burn the book.  _ “…such interesting subjects?” _ he added, like it had been a point of curiosity ever since Sans had first brought the reading material to his restaurant.

Sans shrugged again, this time evasively. “uh… alphys wanted me to look into a couple things,” he mumbled, taking another book and opening it towards the middle with a furrow in his brow.

If he had been paying attention, he would’ve recognised which book Grillby had picked up. So while the fire monster curiously flipped through a few pages, Sans didn’t understand the meaning of Grillby’s question when he asked, already absorbed in the heaps of text.

_ “…skeleton monster?” _

It was the tail-end of the question again, making Sans only stare at him in response. Grillby made a point to hide his smirk with fire as not to cause embarrassment. He was actually very curious.

“what about-?” Sans let the rest of it hang, unsure. Then his eye lights blinked out when the fire monster held up a loose page.

It was the diagram Alphys had included with the textbooks. The fire monster was too quick for Sans to react as fast as he wanted to. Sans tried to lean forward and grab it from him, but Grillby held it away from him as he inspected it, smirking a little. Embarrassed, Sans felt the heat of shame build up under his eyes, but he held his ground. It was just a matter of time before Grillby teased him.

_ “I said,” _ Grillby repeated very carefully,  _ “is this… one of you?” _

There was a way to save this, Sans supposed. As awkward as he felt, he gave a soft sigh as he thought it through.

“nah.”

Grillby brought it down to examine, no longer holding it out of Sans’ reach. Sans thought he looked almost studious. If not for the obstructing flames, he would’ve seen Grillby’s gaze switch between the drawing and himself, as if to draw a comparison.

_ “It… looks the same.” _

Sans tensed a little more. He wasn’t sure why he felt defensive or maybe even a little insulted. “it’s different,” he replied, quieter this time. Grillby watched him with a steady gaze now, page in hand, the hum of his blaze the only sound between them.

Admittedly, Sans studied the page again on his own, mostly the hand on the reverse. While it was similar in shape, there were actual differences between his body and the one on the paper. Conversely, he had tried to find similarities, but they were just as elusive. The only apparent common factor seemed to be that it shared the overall general shape and was comprised of bones.

He must’ve stayed silent for a bit longer than he thought, as Grillby had taken to looking at the page again, this time on the reverse.

_ “…Hand is different, perhaps?” _ It seemed like an innocent enough question.

Carefully, Sans nodded and unballed his left hand, holding it in the space between them. It was innocent, he kept telling himself. Other than Papyrus, he supposed Grillby couldn’t have met any other skeletons. Additionally, Sans had to admit he was curious about the fire monster as well.

He bent his phalanges, each bone clicking faintly as his magic manipulated everything. The movement was so conscious that Sans felt a bit foolish for it, but Grillby watched it all with an air of patience. He didn’t make fun of him for it. He wouldn’t, Sans knew. He would maybe tease, but that was all.

Grillby reached over to put his own hand under Sans’ and he stopped moving his fingers, awaiting more questions. Then Grillby turned the page over, studying it carefully while he lightly moved his own hand up Sans’ radius. It seemed deliberately slow, like a caress. Sans wasn’t used to such a gesture, even with the fire monster’s forward nature. Especially not on his arms, for that matter.

Sans couldn’t repress the subtle shudder that trickled up his shoulder and down his spine as Grillby’s hand moved up to his elbow, giving it a light squeeze.

_ “…This is different,” _ the fire monster added after the brief silence.

His soul trembling at the flood of warmth there, Sans only nodded wordlessly. As though it had never occurred to either of them simply because the notion was so bizarre, they continued to explore. Grillby finally set the page down on the mattress and took Sans’ hand with his own and turned it over, watching as the bones that made up Sans’ wrist shifted to accommodate the movement.

“…am i really that interesting?” Sans couldn’t help but joke. He still felt a little awkward, like he didn’t deserve such rapturous attention. It wasn’t quite the same, but the inspection made him think of his recovery time after the CORE accident, when Alphys and Papyrus would make sure there was no speck of dust to be found. But Grillby’s touch was more tender and didn’t remind him too much of the trauma.

_ “Very,” _ Grillby replied without hesitation.

Sans laughed, then he gestured vaguely to the paper with his other hand. “i mean… i guess i could show you,” he offered, feeling oddly braver for it. “the collar area’s different. ribs. spine.” Sans waited a moment before boldly hooking his fingers behind his neck and pulling his shirt over his skull, depositing it at his side when Grillby let him go.

There really was nothing to it. It was innocent, he told himself. Sans didn’t feel necessarily bashful, but at the same time he was sure Grillby hadn’t been expecting him to strip down… That is, until he noticed the vague, golden hue tinge his flames. Sans’ grin became a little impish then.

“what?”

Grillby only shook his head, the attention giving rise to even paler flames. Sans grinned openly now, excited that he could fluster Grillby again. And to think it only took the sacrifice of his shirt! Sans’ shoulders shook with the chuckles he tried to suppress.

“ok then. see here?” Sans made sure that Grillby was watching as he gestured to his left side, the elbow bending and the bones in his shoulder moving to glide into the new position. He then pointed to the stiff-looking creature depicted on the page, to approximately the same area. “this thing can’t move like this.”

The fire monster seemed to consider it and even glanced up to compare Sans to the drawing again. He remained a shade or two paler than usual, but he was calm and quiet as the skeleton continued.

“the spine’s different,” Sans added, sliding his arm out of Grillby’s grasp again so he could turn slightly to show him. Every hooked vertebra spread and moved as he did, whereas the drawing looked immobile, with clearly not so many bones. Sans’ ribs were wider and fewer, his sternum narrower with a few more pieces. Every bone was paler than the old, yellowed drawn figure. Comparably, Sans even looked softer.

When Sans turned back to a more comfortable sitting position, he watched as Grillby seemed to take in the sight. “what about you, now?” he suddenly asked, his own curiosity getting to the better of him. “it feels like… i dunno. up until recently i kinda thought you were an elemental.”

Grillby shifted to better face Sans, crossing one leg underneath him as he slouched. He reached for Sans’ hand again. When Sans automatically offered his left, Grillby took his right instead. Small, curious flames rolled around the fire monster’s grasp, encircling his bones.

_ “Close,” _ Grillby agreed, his voice quiet.  _ “…Can shift. Not much.” _ He turned his hand, the shape of it enveloped by subtly roiling flames. Then the fingers melded together, returning to Grillby’s preferred shape after his wrist turned in a full rotation. Sans was so captivated that he hadn’t realised that he had leaned forward for a better view.

“cool.”

Sans saw the way the fire monster reacted to his comment again. Slowly, he splayed the fingers of his right hand against Grillby’s forearm, giving it a gentle push as though to test it. It yielded a little, as Grillby’s body was semi-permeable and sank into the spaces between his bones. As a result, flames sputtered around Sans’ fingers as though they were hesitant to be close, but curious in their exploration.

“is… this ok?”

Grillby watched it all very closely. The flames’ reaction to Sans’ touch could have been called something along the lines of a shiver. Whatever type of magic skeleton monsters were made of, Sans’ body set off subtle little notes of nothingness, an absence of heat that Grillby had learned by being around Sans. With closer contact still, Grillby nodded his consent and Sans visibly relaxed.

Sans grew a little bolder and passed his hand up the same arm he was holding to Grillby’s shoulder, just over the fabric of his shirt. As though reconsidering his idea, Sans shoved aside the pile of books with his other hand so he could kneel in front of Grillby unimpeded. With the paler flames up close, Sans gave Grillby a sheepish grin with the fire monster’s questioning aura.

“humour me, g.”

_ “Likewise.” _

The tone made Sans flush, the bloom of his magic plain as day as it crept up from behind his exposed ribs. Curiously, Grillby reached and gently brushed Sans’ sternum with his fingertips, rewarding him with a shift in the glow.

Immediately, Sans’ eye lights darted down with the touch, but he couldn’t help but lean forward just a little. The warmth flooded his rib cage, heavy and hot, but the flames kept a respective distance from his soul. It was like a soothing, fluttering ache, concentrated deep in his bones.

“warm,” he automatically murmured. Sans recognised the quiet rasp from Grillby as a laugh when he moved his own hand to press over the fire monster’s torso. His hand wasn’t pushed away, the heat tingling his fingers. “really warm.”

_ “You’re not,” _ Grillby commented, his touches gentle as they curled against bone, careful not to handle Sans too roughly. Sans’ poor health was always at the back of his mind ever since Papyrus had informed him of it, but if Sans had lived for this long, Sans was stronger than he appeared. Grillby didn’t have to worry too much, he figured.

“it must be weird for you.” There was a calming sigh to Sans’ voice that tugged at Grillby, coupled with his touch that went back up to his shoulder.

_ “It is.” _ Grillby inhaled sharply with the flutter of Sans’ innate magic against the ridges around his shoulder.

“i wonder if all skeletons are like this,” was the idle curiosity that passed Sans’ teeth. “or, uh, were.”

_ “…Do not appear to be sure.” _

“i’m still learning.” He sighed again, soothed relief behind the breath as Grillby moved his hand upwards and lightly traced the pad of his thumb along his clavicle. “a lot of ch.. changes lately.”

_ “Fangs,” _ the fire monster noted, interest in his voice.  _ “A tongue.” _ Lightly. Sans’ soul flickered, drawing Grillby’s gaze down again.  _ “…And a skeleton who blushes.” _

“no.. no making fun, man. i’m just as puzzled as you.” Even as he protested, Sans sounded distracted. As the fire monster’s flames slowly crept up his right arm, the spread of fire sent a hot tingling up through Sans’ shoulders. He shuddered briefly while the heat glowed against his arm, thick like a blanket. Sans couldn’t believe how Grillby could remain so calm while it took everything he could muster not to mentally flatline at the exploration.

_ “Gave me a start,” _ Grillby admitted quietly, then exhaled hotly as Sans’ roaming hand found the side of his neck. His fire crackled in mild protest before resettling, though Sans suddenly looked unsure at the reaction.  _ “Thought that perhaps I had broken your face by accident.” _

It was a funny way to phrase it, but Sans forced a grin with a joke that came to mind. “you thawed me out with that hot smooch,” he murmured, then felt a little more foolish for it when he saw the crack of Grillby’s smile curl into a knowing smirk. That expression coupled with the increasing butterfly feeling in the centre of his chest made Sans feel all the more nervous. “we could… give it another shot.”

Grillby’s hand curled against the base of his skull, flooding him with more fire and eliciting such a tremble from him that Sans couldn’t suppress the clatter of bones. He hummed softly, leaning into the touch. As much as each caress surprised him, he didn’t want Grillby to stop, starved for physical touch beyond hugs and pats from his family.

_ “…Thought you were supposed to be studying?” _ There was that playful teasing tone again.

“i am.” No, he wasn’t. “i’m in the middle of researching this.” With Grillby’s inquisitive look, Sans shifted a little closer, experimentally grazing his fingertips against the fire monster’s back for any reaction. “i gotta prove my, uh… hypothesis.”

Smooth.

A subtle flutter passed through the fire monster’s body, shifting from orange and red, to a flare of amber and back again. Maybe Grillby took the hint, as the fire slipped from his right arm and Grillby’s arms encircled him. Sans couldn’t help but gasp once more as heat flooded up and down his spine. When the fire monster’s hand found the lower vertebrae, Sans’ body gave an involuntary jerk.

_ “…You jump,” _ Grillby observed carefully. His tone made it sound as though he already knew his touch would do that, even before his tease earlier that day. Sans’ mind clouded with the thought of where Grillby’s hands were, giving in to a soft huff in acknowledgment. 

“y.. y’know, that’s not part of the problem statement,” Sans stammered to continue, ignoring the observation as he ghosted his hands down the length of Grillby’s arms, stopping at his wrists.

The movement brought on another hue shift from the fire monster and Sans couldn’t help but grin in thinly veiled triumph.

_ “…What must I do in order to provide assistance?” _

Sans exhaled again, as a bubble of nervousness crept through his bones, picking up excitement along the way. “uh, gathering… empirical data.” With Grillby’s look, Sans felt hot -- and not just because he was in the warm embrace of a fire monster, either. 

Grillby seemed to either understand or feel the need to be closer. Soon, their faces were only a hair’s breadth away and the only thing keeping them from continuing was Sans’ rattling. Grillby took it as a case of the nerves, but he found that those noises weren’t particularly exclusive to being flustered lately.

_ “You’re the scientist… you’ll have to be the one to experiment.” _

Sans inwardly groaned at the tease and moved so he could bring his arms up to encircle around Grillby’s shoulders. He hesitated, a lump of magic coiling in his chest at how close they definitely were now. He could feign courage, if Grillby let him. He could do this.

“heh… jeez.”

_ “…I apologise,” _ Grillby pulled away slightly, like he wanted to see Sans’ reaction.  _ “Like to make you squirm.” _

“stop quoting my embarrassing texts, man.”

To prevent himself from getting side-tracked, Sans settled down so they were at equal heights. His soul pounded with nervousness and anticipation, since it had been Grillby who introduced him to the concept of a kiss in the first place. Sans drew in a soft huff to prepare himself, the flames catching with the breath and he pressed their mouths together.

If he could compare the two, nothing was or would ever be like their first kiss in the bar. This one was so much more different. It sparked in pillowing magic, less hesitant than the first but more exciting the more that followed. Sans moved to bring them closer, dipping his reach under Grillby’s shirt and down the middle of his back.

The fire monster inhaled again against the kiss with surprise to the touch. Sans felt something there. Grillby’s body trembled as though he was actively resisting something, all while his slow kisses were tender and gentle.

Grillby kept his hands unusually still. He refrained from reaching out and even closed his eyes as Sans kissed him. The curl of his smile quirked as Grillby tried his damnedest to behave, leaning into the kiss as his hands twitched to return the touches. He curled his fingers at his ankle between them, his flames caught off guard and excited as the skeleton’s innate magic sent them scattering around his body.

Filled with cushiony sighs, Sans pressed against the fire monster so closely that their souls felt like they were thrumming in tandem. Both of their breaths were deep and shared the air between them, their brows touching. Sans offered Grillby something of a charming smile, looking almost drunk on kisses.

“you didn’t touch back.” His tone was almost disappointed.

It took Grillby a moment to compose himself but opened his eyes with a playful smirk.  _ “…Was not sure if I was permitted to interfere with very serious results.” _

Sans inhaled softly, faltering against his plans. “i mean-”

_ “Comparative testing?” _ Grillby murmured, moving to caress Sans’ jaw with his mouth.  _ “Such a fancy term for kissing.” _

The skeleton leaned into it, his mouth hanging open just as Grillby’s trail of kisses moved down. The nip he was given sent a jolt through his spine like electricity and Sans couldn’t help the weighted gasp that escaped him.

“e-easy,” he murmured, the word both breathless and hazy. His phalanges slipped up Grillby’s back, gently raking through the flames that heated them. His mind was starting to blank out at the attention to his bones; he could barely form coherent thought let alone continue with whatever his original plan was.

_ “…Another one is mine,” _ the fire monster laughed against his neck.  _ “My contribution to… science.” _

A small wisp of steam wafted up from the corner of Sans’ eye. Grinning, he tilted his head towards Grillby in a half-hearted attempt to get him to stop. “c’mon man, i already don’t know how i’m gonna explain this to my bro…”

_ “He’s a clever boy… he’ll know what hijinks you’ve been indulging in.” _

Sans could’ve sworn he felt his entire body flush with the thought -- and with the ruthless teasing he would be subjected to as a result. He bit back a sound locked away in his chest as Grillby went lower, his hot mouth closing over Sans’ clavicle with an accompanying hiss as the moisture in the bone steamed off.

After a moment, Grillby leaned back to inspect the small singe. His smirk was apparent and his flames flickered adoringly between amber and orange as Sans recovered and moved his bony fingers to each side of the fire monster’s neck.

“one more,” the skeleton sighed, already leaning forward again with the need for another kiss.

He caught the hitch of breath that came from Grillby’s mouth as he hesitantly introduced their tongues and soon Sans’ mind was reeling with heat and passion. To his credit, the fire monster played along, allowing him to explore the hot recesses of his mouth with muffled moans of pleasure.

It did something to him, to Sans’ magic, making it ping off in different directions all throughout his body. Sans couldn’t keep his fingers from sliding down from Grillby’s neck, aching for a little more touch that Grillby just wasn’t providing. Sans averted his eyes when the kiss finally broke, panting softly as he focused on the fiery hands clamped dutifully around Grillby’s ankle.

“y.. you really… didn’t wanna mess with my results, huh.” Sans couldn’t keep the bitter tone out of his voice and he grimaced awkwardly. The fire monster grinned, then sneaked a gentle caress against his knee, the circular movement slow and deliberate. “w.. what if i-” Sans decided against further explanation and pushed forward again, having gained a second wind.

Grillby kissed back this time. Where Sans’ tongue was hesitant, shy and his movements excited far too quickly, the fire monster was firm and bold while still remaining sweet. Sans felt the ache build up in him, moaning softly against the kiss as he pressed forward again. When Grillby’s hands found the bends of his knees, it felt like the fire monster was guiding him.

Along with the spicy heat, Grillby’s tongue pressed in, small circular movements against his own. Unable to stop the noise, Sans couldn’t suppress the needy whimper and the tingling shudder that accompanied it.

He dug his fingertips against the fire monster’s body as Grillby’s palms moved up from his knees, circling to the back of his femurs with a light press that left Sans panting in the wake of another successful ‘test’. Sans’ rib cage heaved and he couldn’t help the soft noises he made with every gasp for breath.

Grillby breathed just as urgently. He gave the skeleton an appreciative look, caressing his mouth with his own as he murmured;  _ “…Test results say?” _

“um. in.. inconclusive,” was all Sans could breathe out, still panting but grinning deviously all the same. He was mildly amused when Grillby bodily pulled him forward, then in the same movement pulled back a little so Sans leaned over Grillby, stealing another softer kiss as trails of flames danced around his arms. 

It really was a great way to gather data, Sans hazily thought through the next kiss. He didn’t jerk in shock nearly so badly as before when Grillby’s hand settled on his spine. Sans was too far gone to actually care about where anything went, content as long as they could continue like this. He gave in to another moan and pushed forward again, then moved to adjust his legs to hug either side of Grillby’s waist.

He really wanted to continue -- was even  _ desperate _ to. It should’ve clicked somewhere in Sans’ touch-starved body that Grillby’s fire didn’t make the noises he vaguely heard from the floor. It had been such a constant sound that he had just tuned it out, hungry for more affection as it sunk lower into his body like a warm pulse.

So the hair-splitting sound of glass breaking and shattering across the room effectively startled Sans, enough to inhale sharply and with it a few errant flames. Sans darted up like a shot, legs straddling Grillby’s hips as he stared at the mess of snow and shards of glass on the floor. He stayed in mortified silence, his eye sockets blanked as the gears grinded to a halt in his head.

Then, predictably, came his brother’s booming voice; “WHOOPSY DOOPSY!! MISTER GRILLBY! I HEARD YOU WERE INJURED! ARE YOU ALRIGHT? IS SANS UP THERE?? OF COURSE HE IS. WHY AM I EVEN ASKING?? TELL HIM TO COME DOWN!!”

Sans shrank down. Whatever the mood had been, it certainly was extinguished now. Grillby’s fire tinged paler with his own surprise, but sparks and embers came off of him as he tried not to laugh too loudly.

Meanwhile, the skeleton wanted to hide, his soul pounding so fast like it was going to burst. If the crazy few that were left in Snowdin didn’t know that he and Grillby were together, they were  _ sure _ to know with Papyrus’ rather explosive announcement now.

**Notes for the Chapter:**

> Happy Valentine's Day :'D I think this chapter is rather sweet... and of course Sans is starting to get a little more confident with touches and kisses. Grillby is equally curious about Sans too - a monster that doesn't burn near him? That's pretty interesting, if you think about it.
> 
> Initially I had other plans for Sans but then uh... he hijacked and does his own thing. Papyrus wasn't meant to be a cockblock (he was actually contacting Sans throughout his stay. And also Grillby!) He's a very caring brother.
> 
> Shame 'bout that window, though. I'm sure Grillby gets a deal on windows for the frequency in which they're broken. XD
> 
> Next chapter: Papyrus gives Sans 'The Talk'. ಠ_ಠ


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